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                       SECURITIES AND EXCHANGE COMMISSION

                             WASHINGTON, D.C. 20549

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                                   FORM 10-K

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<C>        <S>
   /X/     ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
           SECURITIES EXCHANGE ACT OF 1934
</TABLE>

                  FOR THE FISCAL YEAR ENDED DECEMBER 31, 1999
                                       OR

<TABLE>
<C>        <S>
   / /     TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
           SECURITIES EXCHANGE ACT OF 1934
</TABLE>

                          Commission File No. 0-27436

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                          TITAN PHARMACEUTICALS, INC.

             (Exact name of registrant as specified in its charter)

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<S>                                            <C>
               DELAWARE                                     94-3171940
    (State or other jurisdiction of              (I.R.S. employer identification
    incorporation or organization)                           number)
</TABLE>

    400 OYSTER POINT BLVD., SUITE 505, SOUTH SAN FRANCISCO, CALIFORNIA 94080
          (Address of principal executive offices, including zip code)

                                 (650) 244-4990
              (Registrant's telephone number, including area code)

          SECURITIES REGISTERED PURSUANT TO SECTION 12(B) OF THE ACT:
                                      None

          SECURITIES REGISTERED PURSUANT TO SECTION 12(G) OF THE ACT:
                         Common Stock, $.001 par value

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    Indicate by check mark whether the registrant: (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding twelve (12) months (or for such shorter period that
the registrant was required to file such report(s)), and (2) has been subject to
the filing requirements for the past ninety (90) days. Yes /X/  No / /

    Indicate by check mark if disclosure of delinquent filers pursuant to Item
405 of Regulation S-K is not contained herein, and will not be contained, to the
best of registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K /X/.

    The aggregate market value of the voting stock held by non-affiliates of the
registrant was approximately $914 million, based on the last sales price of the
common stock as of March 24, 2000.

    As of March 24, 2000, 25,550,075 shares of common stock, $.001 par value, of
the registrant were issued and outstanding.

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                                     PART I

    Statements in this Form 10-K that are not descriptions of historical facts
are forward-looking statements that are subject to risks and uncertainties.
Actual results could differ materially from those currently anticipated due to a
number of factors, including those set forth under "Risk Factors" including, but
not limited to, the results of research and development efforts, the results of
pre-clinical and clinical testing, the effect of regulation by the United States
Food and Drug Administration (FDA) and other agencies, the impact of competitive
products, product development, commercialization and technological difficulties,
the results of financing efforts, the effect of our accounting policies, and
other risks detailed in our Securities and Exchange Commission filings.

    Spheramine-TM-, CeaVac-Registered Trademark-, TriAb-Registered Trademark-,
TriGem-TM-, Pivanex-TM- and CCM-TM- are trademarks of Titan Pharmaceuticals,
Inc. Zomaril-TM- is a trademark of Novartis Pharma AG. This Form 10-K also
includes trade names and trademarks of companies other than Titan
Pharmaceuticals, Inc.

ITEM 1. BUSINESS

(A) GENERAL DEVELOPMENT OF BUSINESS

    Titan Pharmaceuticals, Inc. is a biopharmaceutical company developing
proprietary therapeutics for the treatment of central nervous system (CNS)
disorders, cancer, and other serious and life threatening diseases.

    In the CNS arena, we are developing iloperidone, which is currently in Phase
III clinical testing for schizophrenia through a licensing and development
agreement with Novartis Pharma AG. Novartis has tradenamed the product Zomaril.
Novartis is fully funding and conducting the Phase III program, which will
enroll approximately 3,300 patients in 24 countries. Zomaril is being developed
for the treatment of schizophrenia and related psychotic disorders--a market
expected to reach $6 billion by 2003. Also in the CNS arena, we are developing a
unique cell based therapeutic, Spheramine, which is in Phase I/II testing, for
the treatment of Parkinson's disease. We have entered into a collaboration with
Schering AG for the development, manufacture and commercialization of this
treatment for Parkinson's disease, and Schering is funding the manufacturing,
development and clinical studies of the product in exchange for worldwide
commercialization rights.

    Our cancer therapeutics in clinical testing include three monoclonal
antibodies--CeaVac, TriAb, and TriGem--which are designed to stimulate a
patient's immune system against various types of cancer cells. CeaVac is
currently being evaluated in a large multi-center double-blind
placebo-controlled Phase II/III clinical trial in patients with Stage IV
metastatic colorectal cancer. TriAb is currently being evaluated in a
double-blind placebo-controlled Phase II clinical study in patients with breast
cancer. TriGem has completed initial Phase I testing in patients with melanoma,
and we are pursuing later stage clinical trials through co-operative clinical
oncology research groups. Another Titan anti-cancer product in development,
Pivanex, is a small molecule drug that acts as a cell differentiating agent.
Pivanex is currently in Phase II clinical testing for non-small cell lung
cancer. Additionally, we are developing a gene therapy product for treating
various cancers. Further, we are developing a long-term drug delivery system
with applications in the treatment of CNS disorders and other condition.

    We were incorporated in Delaware in February 1992 and have been funded
through various sources, including our initial public offering in January 1996
and private placements of our securities, as well as proceeds from warrant and
option exercises, corporate licensing and collaborative agreements, and
government sponsored research grants.

    Our gene therapy and long term drug delivery technologies are being
developed in our two consolidated subsidiaries: Ingenex, Inc., and ProNeura,
Inc., respectively. References to us and our products throughout this document
include the products under development by the two subsidiaries.

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(B) FINANCIAL INFORMATION ABOUT INDUSTRY SEGMENTS

    We operate in only one business segment, the development of
biopharmaceutical products.

(C) NARRATIVE DESCRIPTION OF BUSINESS

PRODUCT DEVELOPMENT PROGRAMS

    ZOMARIL (ILOPERIDONE)--SCHIZOPHRENIA AND RELATED PSYCHOTIC DISORDERS

    In January 1997, we entered into a license agreement with Hoechst Marion
Roussel, Inc., pursuant to which we acquired an exclusive worldwide license to
iloperidone, an antipsychotic agent in development for treatment of
schizophrenia and related disorders. Schizophrenia strikes relatively early in
adult life and is generally viewed as a chronic, long-term disorder.
Schizophrenia is characterized by the presence of "positive" symptoms, such as
delusions, hallucinations, and disorganized speech, and "negative" symptoms such
as withdrawal and apathy. According to the World Health Organization,
approximately 45 million people worldwide have some form of schizophrenia or a
related psychotic disorder.

    Zomaril (iloperidone) is one of a new class of antipsychotic medications,
referred to as atypical antipsychotics, which are believed to be more effective
against most of the symptoms of schizophrenia with a lower incidence of side
effects than older medications. The results of Phase II trials, as well as
preliminary data from the Phase III study, demonstrate that Zomaril may provide
effective treatment against symptoms of schizophrenia, with lower incidence of
extrapyramidal symptoms and other significant side effects.

    In November 1997, we entered into an agreement with Novartis Pharma AG in
which we granted a sublicense to Novartis for the worldwide (with the exception
of Japan) development, manufacturing and marketing of Zomaril. Pursuant to the
Novartis sublicense, Novartis paid us approximately $17.4 million in license
fees and reimbursement of research and development expenses and made a $5
million equity investment in us, and is required to make additional milestone
and royalty payments to Hoechst and us. Novartis commenced its Phase III program
for Zomaril in August 1998 and expects to complete all studies by mid 2001.

    IMMUNOTHERAPEUTICS--CANCER THERAPY

    We are engaged in development of cancer immunotherapeutics utilizing
anti-idiotypic antibody technology licensed from the University of Kentucky
Research Foundation. These monoclonal antibody therapeutics under development
mimic specific antigens that are primarily present on the targeted cancer cell
and are not commonly found on normal tissue. From a molecular biological
perspective the antibody is structurally similar to the cancer antigen. When
injected into a patient, the vaccine acts as a trigger for the normal immune
system's response of lymphocytes to attack cancer cells.

    We are developing three such products that have collectively demonstrated an
immune response in humans against antigens associated with colon cancer, breast
cancer, ovarian cancer, small cell lung cancer, melanoma and other cancers. The
products are:

    - CeaVac--We believe this product has potential utility in the treatment of
      adenocarcinomas, notably, colorectal cancer, non-small cell lung cancer,
      pancreatic cancer, gastric cancer and other cancers. The target,
      carcinoembryonic antigen, is presented in the largest group of cancers,
      adenocarcinomas. In particular, this product has received significant
      interest in the international oncology community, as it is the first
      published report of a vaccine to consistently break carcinoembryonic
      antigen immune tolerance in humans. CeaVac is currently being evaluated in
      a multi-center double-blind placebo-controlled Phase II/III clinical trial
      in patients with Stage IV metastatic colorectal cancer. We are also
      pursuing additional clinical studies through co-operative groups.

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    - TriAb--We believe this product has potential utility in the treatment of
      breast, ovarian and non-small cell lung cancer. TriAb is currently being
      evaluated in a double-blind placebo-controlled Phase II clinical study in
      patients with breast cancer.

    - TriGem--We believe this product has potential utility in the treatment of
      melanoma, small cell lung cancer and sarcoma. TriGem has completed initial
      Phase I testing in patients with melanoma, and we are pursuing later stage
      clinical trials through co-operative clinical oncology research groups.

    PIVANEX--ANTI-CANCER THERAPY BASED UPON CELLULAR DIFFERENTIATION

    Pivanex is made from a patented analog of butyric acid and has demonstrated
in laboratory tests the ability to destroy cancer cells through the mechanism of
cellular differentiation. Traditional cytotoxic chemotherapeutics tend to kill
cancer cells preferentially because cancer cells divide more often and more
rapidly than most normal cells. Unfortunately, such agents may also kill rapidly
dividing normal cells, including blood cells and cells of the intestine lining,
which leads to side effects such as anemia, nausea, vomiting and risk of
infection. Unlike traditional cytotoxic chemotherapy, differentiation therapy
represents a relatively new direction in cancer research, and involves the
development of agents that, in contrast to the function of cytotoxic agents,
induce cancer cells to differentiate and undergo terminal cellular senescence.
Differentiation therapy may also lead to apoptosis, or what is known as normal
"programmed cell death," resulting in the destruction of the cancer cells while
sparing normal cells. Pivanex is currently in Phase II clinical testing in
patients with non-small cell lung cancer.

    CELL THERAPY PRODUCTS (SPHERAMINE)--PARKINSON'S DISEASE

    We are engaged in the development of cell-based therapeutics intended for
use in the treatment of neurologic diseases. A majority of neurological
disorders, including Parkinson's disease, Alzheimer's disease, stroke and
epilepsy, occur when brain cells (neurons) die. Because neurons cannot readily
regenerate in response to injury or cell death, most current pharmaceutical
therapies are directed toward amplifying the function of the remaining neurons,
an approach which becomes less effective over time as an increasing number of
the neurons die. In addition, because traditional drugs are delivered through
the blood stream to all body tissues, even though they are intended to act on
only certain sites in the brain, side effects result from the delivery of the
agents to these other non-target organs and tissues. Our proprietary
technologies enable the development of cell-based therapies for
minimally-invasive, site specific (i.e., stereotaxic) delivery to the central
nervous system of therapeutic factors precisely where they are needed in order
to treat the neurological disease or disorder.

    One of our technologies, licensed on an exclusive worldwide basis from New
York University, involves the direct implantation into the CNS of microscopic
beads (microcarriers), the surfaces of which are coated with live cells that
secrete therapeutic factors useful in the treatment of certain neurological
diseases. The beads provide a matrix, or surface, to which cells attach and
grow. We believe that this cell-coated microcarrier (CCM) technology can
facilitate site-specific delivery of missing or deficient neurotransmitters and
growth factors to diseased or injured areas of the brain by increasing the
survival and successful engraftment of implanted cells. Our first product under
development based on this technology is Spheramine, consisting of microcarriers
coated with dopamine-producing human pigment retinal epithelial cells, intended
for the treatment of Parkinson's disease. Preliminary evidence of efficacy of
Spheramine has been demonstrated in a validated primate model of Parkinson's
Disease (MPTP monkey model). Based on these promising results and successful
initial safety testing in primates, we initiated Phase I/II clinical testing of
this product in an open-label evaluation of safety and efficacy. This study is
being performed at Emory University.

    In January 2000, we entered into an agreement with Schering AG, under which
Schering and we will collaborate on manufacturing and clinical development of
cell therapy for the treatment of Parkinson's disease. We will receive funding
for development activities, as well as potential reimbursement of certain

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prior research and development expenses. Schering will fully fund, and manage in
collaboration with us, all future pilot and pivotal clinical studies, and
manufacturing and development activities. Under this agreement, Schering
received exclusive, worldwide development, manufacturing and commercialization
rights, and, in addition to the above payments, agreed to pay us a royalty on
product sales. Schering also retains the right to make an equity investment in
us, up to a specified amount, upon initiation of pivotal clinical studies. In
addition to the collaborative development of Spheramine for Parkinson's disease,
Titan and Schering will also mutually explore other potential therapeutic
applications of our CCM technology, under a one year exclusive option granted to
Schering by us.

    GENE THERAPY PRODUCTS--CANCER

    We are currently developing RB94, a gene therapy product for the treatment
of cancer, under an exclusive worldwide license from the Baylor College of
Medicine held by Titan's Ingenex subsidiary. RB94 combines a truncated variant
(p94) of the RB gene, a tumor suppressor gene, with a viral vector. We believe
the form of the RB protein encoded by the RB94 gene therapy product is more
effective at causing suppression of tumor cells than the full-length RB protein,
based on data demonstrating in vitro suppression of numerous tumor types tested
to date, including tumors of the bladder, prostate, cervix, bone, breast, lung
and fibrous tissue. In addition, preliminary experiments indicate the modified
gene is effective in suppressing some cancer cell lines in vitro that continue
to contain the functional native RB gene.

    We are currently testing RB94 in pre-clinical studies of solid tumors in
mouse models, and expect to conduct additional pre-clinical testing in
preparation for pilot clinical trials.

    In July 1999, we announced that our Ingenex subsidiary had entered into a
cross-license agreement with Selective Genetics, under which we will receive
exclusive rights to develop cancer therapies using Selective's proprietary
cancer cell targeting technology in conjunction with RB94. We plan to combine
these technologies to potentially enable systemic anti-cancer gene therapy.

    We own 81% of the outstanding stock of Ingenex.

    IMPLANTABLE DRUG DELIVERY SYSTEM

    We are developing a sustained drug delivery technology with application in
the treatment of a number of neurologic and psychiatric disorders in which
conventional treatment is limited by variability of drug concentration in blood
and poor patient compliance. The technology, which has been licensed from the
Massachusetts Institute of Technology (MIT), consists of a polymeric drug
delivery system that potentially can provide controlled drug release over
extended periods (i.e., from three months to more than one year). The technology
involves imbedding the drug of interest in a polymer, which is then implanted
subcutaneously to provide systemic delivery as body fluids wash over the implant
and the drug is released. This results in a constant rate of release similar to
intravenous administration. We believe that such long-term, linear release
characteristics are highly desirable, avoiding peak and trough level dosing that
poses problems for many CNS and other therapeutic agents.

    In July 1999, we announced that our ProNeura subsidiary had successfully
completed pre-clinical experiments demonstrating long-term drug delivery using
its polymeric drug delivery system. This study, which was supported by an SBIR
phase I grant from the National Institutes of Health (NIH), demonstrated proof
of concept in animal models using an approved antipsychotic agent, by delivering
sustained therapeutic drug levels for periods of greater than four months,
without any adverse effects.

    We are conducting further pre-clinical evaluation of prototype products
through contract research and manufacturing organizations, including evaluation
of this drug delivery system for treatment of drug addiction. This project is
currently supported by an SBIR grant.

    We currently own approximately 79% of ProNeura.

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SPONSORED RESEARCH AND LICENSE AGREEMENTS

    We are a party to several agreements with research institutions, companies,
universities and other entities for the performance of research and development
activities and for the acquisition of licenses relating to such activities.

    ZOMARIL (ILOPERIDONE)

    In January 1997, we acquired an exclusive worldwide license under United
States and foreign patents and patent applications relating to the use of
iloperidone for the treatment of psychiatric and psychotic disorders and
analgesia. The Hoechst agreement provides for the payment of an up-front license
fee in cash and stock of $9.5 million, which we paid in 1997, as well as
additional late stage milestone payments. See "Item 7. Management's Discussion
and Analysis of Financial Condition and Results of Operations." The Hoechst
agreement also provides for the payment of royalties on net sales and requires
us to satisfy certain other terms and conditions in order to retain its rights
thereunder, all of which have been met to date. In November 1997, we granted a
sublicense to Novartis under which Novartis will continue, at its expense, all
further development of Zomaril and will make milestone payments to us equivalent
to our milestone obligations to Hoechst, and will also pay Hoechst and us a
royalty on net sales of the product.

    IMMUNOTHERAPEUTICS

    In May 1996, we acquired an exclusive, worldwide license under certain
United States and foreign patent and patent applications pursuant to a license
agreement with the University of Kentucky Research Foundation. These patent and
patent applications relate to the anti-idiotypic antibodies known as 3H1, 1A7
and 11D10 and their fragments, derivatives or analogs. The Kentucky agreement
requires us to fund research at the University of Kentucky at amounts agreed to
on an annual basis, for the five year period ending November 14, 2001. The
Kentucky agreement provides for the payment of certain license fees as well as
royalties based on net sales of licensed products by us or any sublicensees. We
must also pay all costs and expenses incurred in obtaining and maintaining
patents, and diligently pursue a vigorous development program for the products
in order to maintain our license rights under the Kentucky agreement.

    PIVANEX

    We have acquired, from Bar-Ilan Research and Development Co. Ltd., an
exclusive, worldwide license to an issued United States patent and certain
foreign patents, and patent applications covering novel analogs of butyric acid
owned by Bar-Ilan University and Kupat Hulim Health Insurance Institution. The
Bar-Ilan agreement provides for the payment by us to Bar-Ilan of royalties based
on net sales of products and processes incorporating the licensed technology,
subject to minimum annual amounts commencing in 1995, as well as a percentage of
any income derived from any sublicense of the licensed technology. We must also
pay all costs and expenses incurred in patent prosecution and maintenance. Our
minimum annual royalty for 1999 and thereafter is $60,000.

    We must also satisfy certain other terms and conditions set forth in the
Bar-Ilan agreement in order to retain our license rights, including:

    - the use of reasonable best efforts to bring any products developed under
      the Bar-Ilan agreement to market,

    - the timely commencement of toxicology testing on small and large animals,

    - the development of and compliance with a detailed business plan, and

    - the timely payment of royalty fees.

    All of the above conditions have been met to date.

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    CELL THERAPY PRODUCTS

    We acquired an exclusive, worldwide license under certain United States and
foreign patent applications relating to the CCM technology pursuant to a
research and license agreement with New York University (NYU). The NYU agreement
provides for the payment of royalties based on net sales of products and
processes incorporating the licensed technology, as well as a percentage of any
income it receives from any sublicense thereof. We are also obligated to
reimburse NYU for all costs and expenses incurred by NYU in filing, prosecuting
and maintaining the licensed patents and patent applications.

    We must satisfy certain other terms and conditions of the NYU agreement in
order to retain our license rights. These include, but are not limited to, the
use of best efforts to bring licensed products to market as soon as commercially
practicable and to diligently commercialize such products thereafter. In
January 2000, we granted a sublicense to Schering AG, under which Schering is
funding the continued development of the licensed technology and potential
commercialization of the product candidate Spheramine. We are also entitled to
certain developmental milestone payments and royalty on net sales of the
product.

    In March 1996, we acquired an exclusive, worldwide license under United
States and foreign patent applications relating to the Sertoli cell technology
pursuant to a license agreement with the University of South Florida and the
University of South Florida Research Foundation, Inc. The South Florida
agreement provides for the payment of royalties based on net sales by us or any
sublicensees of products and processes incorporating the licensed technology. We
are also obligated to reimburse South Florida for all costs and expenses
incurred by South Florida in filing, prosecuting and maintaining the licensed
patent rights. We must satisfy certain other terms and conditions of the South
Florida agreement in order to retain our full exclusive license rights. These
include:

    - the development and introduction into clinical trials of at least one
      product within three years of such date and

    - an additional product every two years thereafter until commercialization
      of one product, and

    - the timely payment of license and royalties.

    If we failed to meet these development obligations, the University of South
Florida may convert this exclusive license into a license specific to the
product or products currently under development by us. We have been unable to
meet these development obligations thus far and the University has not exercised
its right to convert the license. We are in discussion with the University on
the terms of the license.

    GENE THERAPY PRODUCTS

    In October 1992, we acquired an exclusive, worldwide license under United
States and foreign patent applications assigned to Baylor College of Medicine
relating to the RB gene, including its use in conferring senescence to tumors
that form the basis of RB94. The Baylor license provides for royalties based on
net sales of products and processes incorporating the licensed technology,
subject to certain minimum annual amounts and a percentage of sublicensing
income arising from the license of such products and processes. Under the Baylor
license, we must:

    - use reasonable best efforts to bring any products developed under the
      Baylor license to market,

    - develop and comply with a detailed business plan,

    - fund research pursuant to the Baylor research agreement,

    - commence a cancer therapy research program,

    - make timely payment of royalty fees, and

    - pay all costs and expenses incurred in patent filing, prosecution and
      maintenance.

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    We are a party to several license agreements with the University of Illinois
at Chicago which granted us the exclusive worldwide license under certain issued
patents and patent applications, including those relating to methods for
preventing multi-drug resistance and the human MDR1 gene. The exclusive nature
of the Chicago licenses is subject in certain instances to certain reservations,
including the use of all or part of the licensed technology for research,
education and other non-commercial purposes. In addition, our rights under the
MDR1 license are subject to a non-exclusive right granted to Glaxo-Wellcome to
transfect cell lines with the MDR1 gene, and to use the transfectants for
research purposes. Glaxo-Wellcome does not, however, have the right to sell or
transfer the transfectants or any derivatives thereof, without the written
authorization of the University of Illinois at Chicago.

    We have acquired an exclusive license from MIT under an issued patent
relating to the use of MDR genes for creating and selecting drug resistant
mammalian cells. The MIT license is subject to prior grants of:

    - an irrevocable, royalty-free, non-exclusive license granted to the United
      States government,

    - non-exclusive licenses granted to Eli Lilly, Inc. and Genetics Institute,
      Inc. for research purposes, and

    - non-exclusive, commercial licenses that may be granted pursuant to options
      granted to Eli Lilly and Genetics Institute to use aspects of the licensed
      technology but only to make products that do not incorporate genes claimed
      in the patent, proteins expressed by such genes or antibodies and
      inhibitors to such genes.

    The MIT license provides for the payment of royalties based on net sales of
products and processes incorporating the licensed technology, subject to certain
minimum annual amounts, a percentage of sublicensing income arising from the
license of such products and processes, and the issuance to MIT of Ingenex's
common stock to MIT. Under the MIT license, we must also:

    - use reasonable best efforts to bring any products developed under the MIT
      license to market,

    - develop and comply with a detailed business plan and

    - make timely payment of license and royalty fees.

    IMPLANTABLE DRUG DELIVERY SYSTEM

    In October 1995, we acquired from MIT an exclusive worldwide license to
certain United States and foreign patents relating to the implantable drug
delivery system. The MIT license required us to invest $1.8 million in operating
capital toward development of products and processes covered by the MIT license
during the two years ended September 1997, of which approximately $1.7 million
has been invested to date. The exclusive nature of the MIT license was also
subject to the condition that an Investigational New Drug (IND) application had
been filed with the FDA by December 31, 1997. MIT has agreed to change the
September 30 and December 31, 1997 dates to December 31, 1999. We are in
discussion with MIT on further extension of these dates. We must also satisfy
certain other usual terms and conditions set forth in the MIT license in order
to retain our license rights thereunder, including payment of royalties based on
sale of products and processes incorporating the licensed technology, as well as
a percentage of income derived from sublicenses of the licensed technology.

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PATENTS AND PROPRIETARY RIGHTS

    GENERAL

    We have obtained rights to certain patents and patent applications relating
to our proposed products and may, in the future, seek rights from third parties
to additional patents and patent applications. We also rely on trade secrets and
proprietary know-how, which we seek to protect, in part, by confidentiality
agreements with employees, consultants, advisors, and others. For risks we face
with respect to patents and proprietary rights, see "Risk Factors--We may be
unable to protect our patents and proprietary rights."

    ZOMARIL (ILOPERIDONE)

    We are the exclusive licensee under the Hoechst license of issued and
pending United States and foreign patents and patent applications related to
iloperidone, including its use in the treatment of psychiatric disorders,
psychotic disorders and analgesia. Prosecution of various divisional and
continuation applications and their foreign counterparts continues
satisfactorily; although it is uncertain whether additional patents will be
granted. We have no knowledge of any matters or issues which would appear to
materially, negatively affect the validity and/or enforceability of the claims
directed to iloperidone in either the issued patents and/or the associated
counterparts that claim the priority of the U.S. patent applications.

    IMMUNOTHERAPEUTICS

    We are the exclusive licensee under the Kentucky agreement of certain United
States and foreign patents and patent applications related to the anti-idiotype
antibodies known as 3H1, 1A7 and 11D10 and their fragments, derivatives or
analogs. U.S. patents have been issued for the composition and method of use of
the 1A7 antibody in April 1997 and the 3H1 antibody in November 1999.
Prosecution of patents covering the 11D10 antibody continues satisfactorily, as
does prosecution of various divisional and continuation applications and their
foreign counterparts for all the antibodies, although it is uncertain whether
additional patents will be granted. We have no knowledge of any matters or
issues which would appear to materially, negatively affect the validity and/or
enforceability of these patent rights.

    PIVANEX

    We are the exclusive licensee under the Bar-Ilan agreement of an issued
United States patent and certain foreign patents, and patent applications
covering novel analogs of butyric acid. Prosecution of various divisional and
continuation applications and their foreign counterparts continues
satisfactorily; although it is uncertain whether additional patents will be
granted. We have no knowledge of any matters or issues which would appear to
materially, negatively affect the validity and/or enforceability of these patent
rights.

    CELL THERAPY PRODUCTS

    We are the exclusive licensee under the NYU license of United States and
foreign patent applications relating to our cell-coated microcarrier technology.
The Patent and Trademark Office has issued two U.S. patents on the core subject
material underlying the NYU license. An Australian patent on the core material
of a patent application underlying the NYU license was granted in May 1996.
Prosecution of various divisional and continuation applications and their
foreign counterparts continues satisfactorily, although it uncertain whether
additional patents will be granted.

    We are the exclusive licensee under the South Florida agreement of United
States and foreign patent and patent applications related to Sertoli cell
technology. In December 1997, a U.S. patent was issued covering a method for
treating Parkinson's disease by stereotoxic implantation of Sertoli cells
directly into the affected area of the brain without the need for
immunosuppression. In October 1998, a U.S. patent was issued covering a purified
and isolated Sertoli cell-secretory cell hybrid. In November 1998, a U.S. patent

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was issued covering the use of Sertoli cells as a facilitator in the
transplantation of therapeutic cells into the brain and spinal cord.

    We are aware of issued U.S. patents and patent applications relating to use
of Sertoli cells in transplantation filed by Research Corporation Technologies.
These patents and applications may affect the ability to practice certain claims
in the issued South Florida patents and pending patent applications. We and
South Florida believe we may have certain rights in the Research Corporation
patents. The exercise of these rights will depend on an inventorship
determination, the outcome of which is uncertain at this time.

    GENE THERAPY PRODUCT--RB94

    We are the exclusive licensee under the Baylor license of United States and
foreign patent applications relating to the RB gene, including its use in
conferring senescence to tumors that form the basis of RB94. Prosecution of
patents covering RB94 continues satisfactorily, as does prosecution of various
divisional and continuation applications and their foreign counterparts,
although it is uncertain whether additional patents will be granted.

    We are aware of the existence of a prior art reference, European Patent
Application 0 259 031 (EP 0 259 031), which discloses a DNA sequence
corresponding to the sequence of the RB94 DNA molecule that is claimed in a U.S.
patent licensed to us from Baylor College of Medicine. The Baylor patent also
contains claims directed to specific expression vectors containing these DNA
molecules. Although a patent is presumed valid, we cannot assure that the claims
of the Baylor patent, if challenged, will not be found invalid. In any event,
given that EP 0 259 031 relates to DNA molecules but not to methods of gene
therapy, the existence of this reference alone would not, as a matter of U.S.
law, be expected to affect the patentability of claims directed to the use of
the RB94 DNA molecule in gene therapy for certain cancers, which gene therapy
claims presently are pending in a related patent application licensed to us from
Baylor.

    IMPLANTABLE DRUG DELIVERY SYSTEM

    We are the exclusive licensee under the MIT license to three United States
and certain European patents relating to an implantable drug delivery system. We
have no knowledge of any matters or issues which would appear to materially,
negatively affect the validity and/or enforceability of these patent rights.

COMPETITION

    The pharmaceutical and biotechnology industries are characterized by rapidly
evolving technology and intense competition. Many companies of all sizes,
including major pharmaceutical companies and specialized biotechnology
companies, are engaged in the development and commercialization of therapeutic
agents designed for the treatment of the same diseases and disorders targeted by
us. Many of our competitors have substantially greater financial and other
resources, larger research and development staffs and more experience in the
regulatory approval process. Moreover, potential competitors have or may have
patents or other rights that conflict with patents covering our technologies.

    With respect to the product candidate Zomaril, several products categorized
as atypical antipsychotics are already on the market. Specifically, Risperidal
sold by Janssen Pharmaceuticals, Zyprexa sold by Eli Lilly, Clozaril sold by
Novartis and Seroquel sold by Zeneca. Competition among these companies is
already intense and Zomaril, expected to be the fifth or sixth such product on
the market, will face severe competition. The success of Zomaril will depend on
how it can be differentiated from products already on the market on the basis of
efficacy, side effect profile, cost, availability of formulations and dose
requirements, among other things.

    With regard to our immunotherapeutic products, we are aware of several
companies involved in the development of cancer therapeutics that target the
same cancers as the products under development by us. Such companies include
Progenics, Biomira, AltaRex, Genentech, ImClone and Glaxo-Wellcome.

                                       10
<PAGE>
    With regard to our CNS technologies, we are aware of several new drugs for
Parkinson's disease that are in pre-clinical and clinical development. Amgen is
pursuing clinical trials in Parkinson's patients with glial derived neurotraphic
factor (GDNF) and is collaborating with Medtronics, Inc. in its delivery to the
CNS. In addition, several well-funded public and private companies are actively
pursuing alternative cell transplant technologies, including Somatix Therapy
Corporation, CytoTherapeutics Inc. and Diacrin, Inc. The technology under
development by Diacrin, Inc. involves using antibodies to eliminate the need for
immunosuppression when transplanting fetal pig cells into Parkinson's patients,
and would directly compete with Spheramine.

    With regard to our gene therapy products, we are aware of several
development stage and established enterprises that are exploring the field of
human gene therapy or are actively engaged in research and development in this
area, including Genetix Pharmaceuticals, Inc. and two research organizations
receiving funding from the NIH. We are aware of other commercial entities that
have produced gene therapy products used in human trials. Further, it is
expected that competition in this field will intensify.

    With regard to our implantable drug delivery system, we are aware of an
implantable therapeutic system being developed by ALZA Corporation.
Additionally, companies such as Medtronics are developing implantable pumps that
could be used to infuse drugs into the CNS.

    In addition to the foregoing, colleges, universities, governmental agencies
and other public and private research organizations are likely to continue to
conduct research and are becoming more active in seeking patent protection and
licensing arrangements to collect royalties for use of technology that they have
developed, some of which may be directly competitive with the technologies being
developed by us.

    See "Risk Factors--We face intense competition."

GOVERNMENT REGULATION

    In order to obtain FDA approval of a new drug, a company generally must
submit proof of purity, potency, safety and efficacy, among others. In most
cases, such proof entails extensive clinical and pre-clinical laboratory tests.

    The procedure for obtaining FDA approval to market a new drug involves
several steps. Initially, the manufacturer must conduct pre-clinical animal
testing to demonstrate that the product does not pose an unreasonable risk to
human subjects in clinical studies. Upon completion of such animal testing, an
IND application must be filed with the FDA before clinical studies may begin. An
IND application consists of, among other things, information about the proposed
clinical trials. Among the conditions for clinical studies and IND approval is
the requirement that the prospective manufacturer's quality control and
manufacturing procedures conform to current Good Manufacturing Practices (cGMP),
which must be followed at all times. Once the IND is approved (or if FDA fails
to act within 30 days), the clinical trials may begin.

    Human clinical trials on drugs are typically conducted in three sequential
phases, although the phases may overlap. Phase I trials typically consist of
testing the product in a small number of healthy volunteers or in patients,
primarily for safety in one or more doses. During Phase II, in addition to
safety, dose selection and efficacy of the product is evaluated in up to several
hundred patients and sometimes more. Phase III trials typically involve
additional testing for safety and confirmation of efficacy in an expanded
patient population at multiple test sites. The FDA may order the temporary or
permanent discontinuation of a clinical trial at any time.

    The results of the pre-clinical and clinical testing on new drugs are
submitted to the FDA in the form of a New Drug Application (NDA). The NDA
approval process requires substantial time and effort and there can be no
assurance that any approval will be granted on a timely basis, if at all. The
FDA may refuse to approve an NDA if applicable regulatory requirements are not
satisfied. Product approvals, if granted,

                                       11
<PAGE>
may be withdrawn if compliance with regulatory standards is not maintained or
problems occur following initial marketing.

    The FDA may also require post-marketing testing and surveillance of approved
products, or place other conditions on their approvals. These requirements could
cause it to be more difficult or expensive to sell the products, and could
therefore restrict the commercial applications of such products. Product
approvals may be withdrawn if compliance with regulatory standards is not
maintained or if problems occur following initial marketing. With respect to
patented products or technologies, delays imposed by the governmental approval
process may materially reduce the period during which we will have the exclusive
right to exploit such technologies.

    In addition, our gene therapy product candidate is subject to guidelines
established by NIH, covering deliberate transfers of recombinant DNA into human
subjects conducted within NIH laboratories or with NIH funds, which provide that
such products must be approved by the NIH Director. The NIH has established the
Recombinant DNA Advisory Committee which sets forth guidelines concerning
approval of NIH-supported research involving the use of recombinant DNA.
Although the jurisdiction of the NIH applies only when NIH-funded research or
facilities are involved in any aspect of the protocol, the Advisory Committee
encourages all gene transfer protocols to be submitted for its review. We intend
to comply with the Advisory Committee and NIH guidelines.

    We believe we are in compliance with all material applicable regulatory
requirements. However, see "Risk Factors--We must comply with extensive
government regulations" for additional risks we face regarding regulatory
requirements and compliance.

FOREIGN REGULATORY ISSUES

    Sales of pharmaceutical products outside the United States are subject to
foreign regulatory requirements that vary widely from country to country.
Whether or not FDA approval has been obtained, approval of a product by a
comparable regulatory authority of a foreign country must generally be obtained
prior to the commencement of marketing in those countries. Although the time
required to obtain such approval may be longer or shorter than that required for
FDA approval, the requirements for FDA approval are among the most detailed in
the world and FDA approval generally takes longer than foreign regulatory
approvals.

EMPLOYEES

    We currently have 30 full-time employees. None of our employees are
represented by a labor union. We have not experienced any work stoppages and
consider our relations with our employees to be good. See "Risk Factors--We may
not be able to retain our key management and scientific personnel."

RISK FACTORS

    An investment in our stock involves various risks. You should carefully
consider the following risk factors and other information incorporated by
reference before deciding to purchase our shares.

    WE HAVE A HISTORY OF OPERATING LOSSES AND MAY NEVER BE PROFITABLE.  Through
December 31, 1999, we had accumulated net losses since inception of
approximately $65.4 million. We will continue to incur losses for the
foreseeable future as a result of the various costs associated with our
research, development, financial, administrative, regulatory and management
activities. We may never achieve or sustain profitability.

    OUR PRODUCTS ARE AT AN EARLY STAGE OF DEVELOPMENT AND MAY NOT BE
SUCCESSFULLY DEVELOPED OR COMMERCIALIZED.  Our proposed products are at various
stages of development, but all will require significant further

                                       12
<PAGE>
development, testing and regulatory clearances prior to commercialization. We
are subject to the risk that some or all of our proposed products:

    - will be found to be ineffective or unsafe;

    - will not receive necessary regulatory clearances;

    - will not be capable of being produced in commercial quantities at
      reasonable costs; or

    - will not be successfully marketed.

    We may experience unanticipated problems relating to product development,
testing, regulatory compliance, manufacturing, marketing and competition, and
our costs and expenses could exceed current estimates. We cannot predict whether
we will successfully develop and commercialize any products.

    WE MUST COMPLY WITH EXTENSIVE GOVERNMENT REGULATIONS.  Our research,
development, pre-clinical and clinical trial activities, and the manufacturing
and marketing of any products which we may successfully develop are subject to
an extensive regulatory approval process by the FDA and other regulatory
agencies in the U.S. and other countries. The process of obtaining required
regulatory approvals for drugs, including conducting pre-clinical and clinical
testing, is lengthy, expensive and uncertain. Even after such time and
expenditures, we may not obtain necessary regulatory approvals for clinical
testing or for the manufacturing or marketing of any products. Regulatory
approval may entail limitations on the indicated usage of a drug, which may
reduce the drug's market potential. Even if regulatory clearance is obtained,
post-market evaluation of the products, if required, could result in
restrictions on a product's marketing or withdrawal of the product from the
market as well as possible civil or criminal sanctions. We depend on
laboratories and medical institutions conducting pre-clinical studies and
clinical trials to maintain both good laboratory and good clinical practices. We
will also depend upon the manufacturers of any products we may successfully
develop to comply with cGMP.

    In addition, we and our collaborative partners may be subject to regulation
under state and federal laws, including requirements regarding occupational
safety, laboratory practices, environmental protection and hazardous substance
control, and may be subject to other local, state, federal and foreign
regulation. We cannot predict the impact of such regulation on us, although it
could be material and adverse.

    WE MAY BE UNABLE TO PROTECT OUR PATENTS AND PROPRIETARY RIGHTS.  Our future
success will depend to a significant extent on our ability to:

    - enforce patent protection on our products and technologies;

    - maintain trade secrets; and

    - operate and commercialize products without infringing on the patents or
      proprietary rights of others.

    Our patents may not afford any competitive advantages and may be challenged
or circumvented by third parties. Further, patents may not issue on pending
patent applications. Because of the extensive time required for development,
testing and regulatory review of a potential product, it is possible that before
a potential product can be commercialized, any related patent may expire, or
remain in existence for only a short period following commercialization,
reducing any advantage of the patent.

    Our business may be materially adversely affected if others independently
develop similar technologies or duplicate any technology we develop.
Furthermore, costly and time consuming litigation may be necessary to:

    - enforce any of our patents;

    - determine the scope and validity of the patent rights of others; or

                                       13
<PAGE>
    - respond to a legal action against us claiming damages for infringement of
      patent rights or other proprietary rights or seeking to enjoin commercial
      activities relating to the affected product or process.

    The outcome of any such litigation is highly uncertain.

    To the extent that consultants, key employees or other third parties apply
technological information independently developed by them or by others to our
proposed products, disputes may arise as to the proprietary rights to such
information which may not be resolved in our favor. Most of our consultants are
employed by or have consulting agreements with third parties and any inventions
discovered by such individuals generally will not become our property. There is
a risk that other parties may breach confidentiality agreements or that our
trade secrets become known or independently discovered by competitors, which
could adversely affect us.

    WE FACE INTENSE COMPETITION.  Competition in the pharmaceutical and
biotechnology industries is intense and is expected to increase. We will face
competition from numerous companies that currently market, or are developing,
products for the treatment of the diseases and disorders we have targeted. Many
of these entities have significantly greater research and development
capabilities, experience in obtaining regulatory approvals and manufacturing,
marketing, financial and managerial resources than us. We also compete with
universities and other research institutions in the development of products,
technologies and processes, as well as the recruitment of highly qualified
personnel. Our competitors may succeed in developing technologies or products
that are more effective than the ones we have under development or that render
our proposed products or technologies noncompetitive or obsolete. In addition,
certain of such competitors may achieve product commercialization or patent
protection earlier than us.

    WE ARE DEPENDENT UPON OUR KEY COLLABORATIVE RELATIONSHIPS AND LICENSE AND
SPONSORED RESEARCH AGREEMENTS. As a small company with limited resources, we
rely significantly on the resources of third parties to conduct research and
development on our behalf. For example, our ability to ultimately derive
revenues from Zomaril is almost entirely dependent upon Novartis conducting the
Phase III trials and completing the regulatory approval process and implementing
the marketing program necessary to commercialize Zomaril if the trials are
successful. Our success in the future will depend, in part, on our ability to
maintain existing collaborative relationships and to develop new collaborative
relationships with third parties. Our license agreements relating to the
in-licensing of technology generally require the payment of up-front license
fees and royalties based on sales with minimum annual royalties, the use of due
diligence in developing and bringing products to market, the achievement of
funding milestones and, in some cases, the grant of stock to the licensor. Our
sponsored research agreements generally require periodic payments on an annual
or quarterly basis. Our failure to meet financial or other obligations under
license or sponsored research agreements in a timely manner could result in the
loss of our rights to proprietary technology or our right to have the applicable
university or institution conduct research and development efforts.

    WE MAY BE DEPENDENT ON THIRD PARTIES TO MANUFACTURE AND MARKET ANY PRODUCTS
WE MAY SUCCESSFULLY DEVELOP.  To date, we have not introduced any products on
the commercial market. We may not have the resources in the foreseeable future
to allocate to the commercial manufacture or direct marketing of any proposed
products. Collaborative arrangements may be pursued regarding the manufacture
and marketing of any products that may be successfully developed. We may be
unable to enter into additional collaborative arrangements to manufacture or
market any proposed products or, in lieu thereof, establish our own
manufacturing operations or sales force.

    WE MAY NOT BE ABLE TO RETAIN OUR KEY MANAGEMENT AND SCIENTIFIC
PERSONNEL.  As a small company with a limited number of personnel, we are highly
dependent on the services of Dr. Louis R. Bucalo, Chairman, President and Chief
Executive Officer, as well as the other principal members of our management and
scientific staff. The loss of one or more of such individuals could
substantially impair ongoing research and

                                       14
<PAGE>
development programs and could hinder our ability to obtain corporate partners.
Our success depends in large part upon our ability to attract and retain highly
qualified personnel. We compete in our hiring efforts with other pharmaceutical
and biotechnology companies, as well as universities and nonprofit research
organizations, and we may have to pay higher salaries to attract and retain
personnel.

    WE MAY NEED ADDITIONAL FINANCING.  At March 15, 2000, we had approximately
$84.7 million of cash which we believe will enable us to fund our operations at
least through 2003. We may need to seek additional financing after such time to
continue our product development activities, and will be required to obtain
substantial funding to commercialize any products that we may successfully
develop. We do not have any funding commitments or arrangements other than our
bank line of credit. If we are unable to enter into a corporate collaboration,
complete a debt or equity offering, or otherwise obtain any needed financing, we
will be required to reduce, defer or discontinue our product development
programs. We may be required to obtain funds on terms that are not favorable to
us and our stockholders.

    FUTURE SALES OF OUR COMMON STOCK IN THE PUBLIC MARKET COULD ADVERSELY IMPACT
OUR STOCK PRICE.  Future sales of our common stock by existing stockholders
pursuant to Rule 144 under the Securities Act, pursuant to an effective
registration statement or otherwise, could have an adverse effect on the price
of our securities.

ITEM 2. PROPERTIES

    We have a four-year lease, expiring in June 2002, for approximately 10,000
square feet of office space in South San Francisco, California. We also have a
five-year lease, expiring in October 2003, for approximately 4,200 square feet
of space in Somerville, New Jersey.

ITEM 3. LEGAL PROCEEDINGS

    We are not a party to any material legal proceedings.

ITEM 4. SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

    Not applicable

                                       15
<PAGE>
                                    PART II

ITEM 5. MARKET FOR REGISTRANT'S COMMON EQUITY AND RELATED STOCKHOLDER MATTERS.

(A) PRICE RANGE OF SECURITIES

    Through November 20, 1998, our common stock traded on the Nasdaq SmallCap
Market under the symbol TTNP. On November 23, 1998, our common stock began
trading on the American Stock Exchange under the symbol TTP. The table below
sets forth the high and low sales prices of our common stock as reported by the
Nasdaq SmallCap Market and the American Stock Exchange for the periods
indicated. For the period during which we were listed on the Nasdaq SmallCap
Market, prices are based on quotations between dealers, do not reflect retail
mark-up, mark-down or commissions, and do not necessarily represent actual
transactions.

<TABLE>
<CAPTION>
                                                                HIGH       LOW
                                                              --------   --------
<S>                                                           <C>        <C>
Fiscal Year Ended December 31, 1999:
  First Quarter.............................................  $ 4.750     $3.250
  Second Quarter............................................  $ 4.938     $2.750
  Third Quarter.............................................  $13.563     $4.313
  Fourth Quarter............................................  $19.500     $6.750
Fiscal Year Ended December 31, 1998:
  First Quarter.............................................  $ 5.750     $4.625
  Second Quarter............................................  $ 6.125     $3.813
  Third Quarter.............................................  $ 5.125     $2.188
  Fourth Quarter............................................  $ 3.938     $1.844
</TABLE>

(B) APPROXIMATE NUMBER OF EQUITY SECURITY HOLDERS

    The number of record holders of our common stock as of March 24, 2000 was
approximately 202. Based on the last ADP search, we believe there are in excess
of 3,000 beneficial holders of the common stock.

(C) DIVIDENDS

    We have never paid a cash dividend on our common stock and anticipate that
for the foreseeable future any earnings will be retained for use in our business
and, accordingly, do not anticipate the payment of cash dividends.

                                       16
<PAGE>
ITEM 6. SELECTED FINANCIAL DATA

    The selected financial data presented below summarizes certain financial
data which has been derived from and should be read in conjunction with our more
detailed financial statements and footnotes thereto included in the section
beginning on page F-1. See also "Item 7. Management's Discussion and Analysis of
Financial Condition and Results of Operations."

<TABLE>
<CAPTION>
                                                           YEAR ENDED DECEMBER 31,
                                             ----------------------------------------------------
                                               1999       1998       1997       1996       1995
                                             --------   --------   --------   --------   --------
                                                   (IN THOUSANDS, EXCEPT PER SHARE AMOUNT)
<S>                                          <C>        <C>        <C>        <C>        <C>
STATEMENT OF OPERATIONS DATA:
Total revenues (1).........................  $    337   $     --   $ 17,500   $    259   $    140
Operating expenses:
Research and development...................     9,429      7,813      9,310      5,567      5,202
Acquired in-process research and
  development..............................       136         --      9,500         --        686
General and administrative.................     2,794      3,708      6,514      5,264      3,658
Other income (expense)--net (2)............       726        907      8,415     (2,294)    (2,288)
                                             --------   --------   --------   --------   --------
Net (loss) income..........................  $(11,296)  $(10,614)  $    592   $(12,856)  $(11,693)
                                             ========   ========   ========   ========   ========
Basic net (loss) income per share (pro
  forma in 1995)...........................  $  (0.70)  $  (0.81)  $   0.05   $  (1.67)  $  (1.74)
                                             ========   ========   ========   ========   ========
Diluted net (loss) income per share........  $  (0.70)  $  (0.81)  $   0.04   $  (1.67)  $  (1.74)
                                             ========   ========   ========   ========   ========
</TABLE>

------------------------

(1) Revenues for 1997 include $17.4 million from fees related to the sublicense
    of Zomaril to Novartis.

(2) Other income for 1997 includes a gain of $8.4 million from the sale of a
    research technology.

<TABLE>
<CAPTION>
                                                              AS OF DECEMBER 31,
                                             ----------------------------------------------------
                                               1999       1998       1997       1996       1995
                                             --------   --------   --------   --------   --------
                                                                (IN THOUSANDS)
<S>                                          <C>        <C>        <C>        <C>        <C>
BALANCE SHEET DATA:
Working capital (deficiency)...............  $ 45,112   $ 10,215   $ 23,642   $ 12,174   $ (6,232)
Total assets...............................    47,362     12,228     25,594     16,366      4,732
Long-term debt.............................        --         --         --      1,200      2,036
Accumulated deficit........................   (65,418)   (54,123)   (43,508)   (44,100)   (31,244)
Stockholders' equity (deficiency)..........    44,302      9,406     17,178     11,411     (5,823)
</TABLE>

ITEM 7. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS
  OF OPERATIONS.

    THE FOLLOWING DISCUSSION SHOULD BE READ IN CONJUNCTION WITH THE CONSOLIDATED
FINANCIAL STATEMENTS AND NOTES THERETO APPEARING ELSEWHERE IN THIS REPORT.

    THE FOLLOWING DISCUSSION CONTAINS CERTAIN FORWARD-LOOKING STATEMENTS, WITHIN
THE MEANING OF THE "SAFE HARBOR" PROVISIONS OF THE PRIVATE SECURITIES REFORM ACT
OF 1995, THE ATTAINMENT OF WHICH INVOLVES VARIOUS RISKS AND UNCERTAINTIES.
FORWARD-LOOKING STATEMENTS MAY BE IDENTIFIED BY THE USE OF FORWARD-LOOKING
TERMINOLOGY SUCH AS "MAY," "WILL," "EXPECT," "BELIEVE," "ESTIMATE,"
"ANTICIPATE," "CONTINUE," OR SIMILAR TERMS, VARIATIONS OF THOSE TERMS OR THE
NEGATIVE OF THOSE TERMS. OUR ACTUAL RESULTS MAY DIFFER MATERIALLY FROM THOSE
DESCRIBED IN THESE FORWARD-LOOKING STATEMENTS DUE TO, AMONG OTHER FACTORS, THE
RESULTS OF ONGOING RESEARCH AND DEVELOPMENT ACTIVITIES AND PRE-CLINICAL TESTING,
THE RESULTS OF CLINICAL TRIALS AND THE AVAILABILITY OF ADDITIONAL FINANCING
THROUGH CORPORATE PARTNERING ARRANGEMENTS OR OTHERWISE.

    SPHERAMINE-TM-, CEAVAC-REGISTERED TRADEMARK-, TRIAB-REGISTERED TRADEMARK-,
TRIGEM-TM-, PIVANEX-TM- AND CCM-TM- ARE TRADEMARKS OF TITAN PHARMACEUTICALS,
INC. ZOMARIL-TM- IS A TRADEMARK OF NOVARTIS PHARMA AG.

                                       17
<PAGE>
OVERVIEW

    We are a biopharmaceutical company developing proprietary therapeutics for
the treatment of central nervous system disorders, cancer and other serious and
life-threatening diseases.

    Our most advanced product candidate, Zomaril (iloperidone), is a novel
antipsychotic agent under development for the treatment of patients with
schizophrenia. Zomaril is currently in Phase III clinical testing through a
licensing and development agreement with Novartis Pharma AG. Also in the CNS
arena, we are developing a unique cell based therapeutic, Spheramine, for the
treatment of patients with Parkinson's disease. In November 1999, we received
approval from the FDA to commence Phase I/II clinical testing with Spheramine.
We have entered into a collaboration with Schering AG for the development,
manufacture and commercialization of this treatment for Parkinson's disease, and
Schering is funding the manufacturing, development and clinical studies of the
product in exchange for worldwide commercialization rights. Our cancer portfolio
includes three therapeutic monoclonal antibodies--CeaVac, TriAb, and
TriGem--that are designed to stimulate a patient's immune system against cancer
cells. CeaVac is currently being evaluated in a large multi-center double-blind
placebo-controlled Phase II/ III clinical trial in patients with Stage IV
metastatic colorectal cancer. TriAb is currently being evaluated in a
double-blind placebo-controlled Phase II clinical study in patients with breast
cancer. TriGem has completed initial Phase I testing in patients with melanoma,
and we are pursuing later stage clinical trials through co-operative clinical
oncology research groups. We are also currently conducting a Phase II clinical
trial with Pivanex, a novel synthetic analog of butyric acid, for the treatment
of patients with non-small cell lung cancer. Our other programs in pre-clinical
development include a cancer gene therapy product and an implantable drug
delivery technology.

RESULTS OF OPERATIONS FOR THE THREE YEARS ENDED DECEMBER 31, 1999, 1998, AND
  1997

    1999 COMPARED TO 1998

    Since inception, we have devoted substantially all of our resources to
product and technology development, clinical research, raising capital, and
securing patent protection. At December 31, 1999, we had an accumulated deficit
of $65.4 million and working capital of $45.1 million.

    Revenues in 1999 of $0.3 million consisted primarily of U.S. government
grants. There were no revenues for 1998.

    From inception through December 31, 1999, research and development expenses,
including $10.3 million in acquired in-process research and development costs,
totaled $64.5 million, and general and administrative expenses totaled $24.8
million. Research and development expenses for 1999 were $9.6 million, including
$0.1 million of acquired in-process research and development related to the
acquisition of the minority interest of Theracell, compared to $7.8 million for
1998, an increase of $1.8 million, or 22%. The planned increase compared to 1998
was attributable to patient enrollment in the clinical trial with CeaVac in
colorectal cancer and the final phases of the pre-clinical program for
Spheramine in preparation for Phase I/II clinical trial. General and
administrative expenses for 1999 were $2.8 million compared to $3.7 million for
1998, a decrease of $0.9 million, or 25%. The decrease was attributable to
ongoing efforts to contain non-research operating costs.

    Other income for 1999 was $0.7 million compared to $0.9 million for 1998, a
decrease of $0.2 million, or 20%. Other income for 1999 and 1998 primarily
consisted of interest income.

    As a result of the foregoing, we had a net loss of $11.3 million in 1999
compared to a net loss of $10.6 million in 1998.

    None of our products have been commercialized, and we do not expect to
generate any revenue from product sales or royalties until at least 2002. With
the advancement in clinical development of our products, we anticipate research
and development expenses will increase in the near future, while general and
administrative costs necessary to support such research and development
activities will increase at a

                                       18
<PAGE>
controlled rate. We will also seek to identify new technologies and/or product
candidates for possible in-licensing or acquisition. Accordingly, we expect to
incur operating losses for the foreseeable future. We cannot assure that we will
ever achieve profitable operations.

    1998 COMPARED TO 1997

    There were no revenues for 1998 compared to $17.5 million for 1997. Total
revenues for 1997 were comprised of approximately $17.4 million from fees
related to the license of Zomaril to Novartis and $0.1 million from U.S.
government grants.

    Research and development expenses for 1998 were $7.8 million, as compared to
$18.8 million for 1997, a decrease of $11.0 million, or 58%. 1997 expenses
include $9.5 million of acquired in-process research and development and other
expenditures related to the acquisition of Zomaril, the development of which is
now being funded by Novartis pursuant to the partnering agreement established by
us and Novartis in November 1997. General and administrative expenses for 1998
were $3.7 million compared to $6.5 million for 1997, a decrease of
$2.8 million, or 43%. The decrease is attributable to the merger of a former
subsidiary with and into Titan in August 1997, with a subsequent reduction in
personnel and other expenses, as well as the reduction in overhead associated
with the sale of a research technology by Ingenex in June 1997.

    Other income for 1998 was $0.9 million compared to $8.4 million for 1997.
Other income for 1998 includes interest income of $0.8 million. Other income for
1997 includes a gain of $8.4 million from the sale of a research technology, net
interest income of $0.4 million, and a loss of $0.6 million representing our
share of the losses of Ansan Pharmaceuticals, Inc., our former subsidiary.

    We had a net loss of $10.6 million in 1998 compared to net income of $0.6
million in 1997.

LIQUIDITY AND CAPITAL RESOURCES

    We have funded our operations since inception primarily through our initial
public offering and private placements of our securities, as well as proceeds
from warrant and option exercises, corporate licensing and collaborative
agreements, and government sponsored research grants. Cash has been used in
operating activities primarily to fund operating expenses.

    In March 2000, we completed a private placement of 1.2 million shares of our
common stock for net proceeds of approximately $38.9 million, after deducting
fees and commissions and other expenses of the offering.

    In October 1999, we called for the redemption on November 19, 1999 (the
Redemption Date) of our outstanding Class A Warrants for cash at the redemption
price of $0.05 per warrant. Rather than surrendering the warrants for
redemption, warrant holders had the option to purchase our common stock at a
price of $6.02 per share before the Redemption Date. The warrant call resulted
in 7.1 million, or 99.4%, of our outstanding Class A Warrants being exercised
with net proceeds to us of $39.4 million, after deducting advisory fees and
other related expenses.

    In January 1999, we completed a private placement of 2.3 million shares of
our common stock for net proceeds of $5.8 million, after deducting fees and
commissions and other expenses of the offering.

    During 1997, we received $25.9 million from license fees related to the
Novartis sublicense and the sale of a research technology.

    In January 1997, we entered into an exclusive license agreement with Hoechst
Marion Roussel, Inc., (Hoechst) pursuant to which we received the worldwide
patent rights and know-how related to the antipsychotic agent Zomaril. During
1997, we paid fees consisting of:

    (i) $4.0 million in cash, and

                                       19
<PAGE>
    (ii) $5.5 million through the issuance of approximately 0.6 million shares
       of common stock (the Hoechst Shares.)

    We were obligated to pay the difference between $5.5 million and the net
proceeds received by Hoechst upon the sale of the Hoechst Shares. In February
1998, Hoechst received net proceeds of $2.5 million on the sale of the Hoechst
Shares. Accordingly, in March 1998, we paid to Hoechst $3.0 million.

    We have entered into various agreements with research institutions,
universities, and other entities for the performance of research and development
activities and for the acquisition of licenses related to those activities. The
aggregate commitments we have under these agreements, including minimum license
payments, for the next 12 months is approximately $1.5 million. Certain of the
licenses provide for the payment of royalties by us on future product sales, if
any. In addition, in order to maintain license and other rights while products
are under development, we must comply with customary licensee obligations,
including the payment of patent related costs and meeting project-funding
milestones.

    We expect to continue to incur substantial additional operating losses from
costs related to continuation and expansion of product and technology
development, clinical trials, and administrative activities. To preserve
operating capital, we have chosen to strategically focus on development of our
later stage products in clinical development, and at least temporarily reduce or
eliminate spending on certain pre-clinical programs. We believe that we
currently have sufficient working capital to sustain our planned operations at
least through 2003.

    Our cash and investment policy emphasizes liquidity and preservation of
principal over other portfolio considerations. We select investments that
maximize interest income to the extent possible given these two constraints. We
satisfy liquidity requirements by investing excess cash in securities with
different maturities to match projected cash needs and limit concentration of
credit risk by diversifying our investments among a variety of high
credit-quality issuers.

YEAR 2000 COMPLIANCE

    In prior years, we discussed the nature and progress of our Year 2000
readiness. In late 1999, we completed remediation and testing of systems at
minimal cost. As a result of those planning and implementation efforts, we
experienced no significant disruptions in mission critical information
technology and non-information technology systems and believe those systems
successfully responded to the Year 2000 date change. We are not aware of any
material problems resulting from the Year 2000 issue, either with our products
under development, internal systems, or the products and services of third
parties. We will continue to monitor our mission critical computer applications
and our suppliers and vendors throughout the year to ensure that any latent Year
2000 matters that may arise are addressed promptly.

ITEM 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

    We have reviewed the requirements of Item 7A and have determined that these
disclosures are not applicable.

ITEM 8. CONSOLIDATED FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA.

    The response to this item is included in a separate section of this Report.
See "Index to Consolidated Financial Statements" on Page F-1.

ITEM 9. CHANGES AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND FINANCIAL
  DISCLOSURE.

    Not applicable.

                                       20
<PAGE>
ITEM 10. DIRECTORS AND EXECUTIVE OFFICERS OF REGISTRANT.

    The following table sets forth the names, ages and positions of our
executive officers and directors.

<TABLE>
<CAPTION>
NAME                                                 AGE      POSITION
----                                               --------   --------
<S>                                                <C>        <C>
Louis R. Bucalo, M.D. (1).......................      41      Chairman, President and Chief Executive Officer
Sunil Bhonsle...................................      50      Executive Vice President and Chief Operating
                                                              Officer
Richard C. Allen, Ph.D..........................      57      Executive Vice President
Robert E. Farrell...............................      50      Executive Vice President and Chief Financial
                                                              Officer
Victor Bauer, Ph.D..............................      64      Executive Director of Corporate Development and
                                                              Director
Ernst-Gunter Afting, M.D., Ph.D. (2)............      57      Director
Eurelio M. Cavalier.............................      67      Director
Michael K. Hsu (2)..............................      51      Director
Hubert Huckel, M.D. (1)(3)......................      68      Director
Marvin E. Jaffe, M.D. (1)(3)....................      63      Director
Konrad M. Weis, Ph.D. (1).......................      71      Director
</TABLE>

------------------------

(1) Member of Executive Committee

(2) Member of Audit Committee

(3) Member of Compensation Committee

    LOUIS R. BUCALO, M.D. is a founder of Titan and has served as our President
and Chief Executive Officer since January 1993. Dr. Bucalo has served as a
director of Titan since March 1993 and was elected Chairman of the Board of
Directors in January 2000. From July 1990 to April 1992, Dr. Bucalo was
Associate Director of Clinical Research at Genentech, Inc., a biotechnology
company. Dr. Bucalo holds an M.D. from Stanford University and a B.A. in
biochemistry from Harvard University.

    SUNIL BHONSLE joined us as Executive Vice President and Chief Operating
Officer in September 1995. Mr. Bhonsle served in various positions, including
Vice President and General Manager-Plasma Supply and Manager-Inventory and
Technical Planning, at Bayer Corporation from July 1975 until April 1995.
Mr. Bhonsle holds an M.B.A. from the University of California at Berkeley and a
B.Tech. in chemical engineering from the Indian Institute of Technology.

    RICHARD C. ALLEN, PH.D., joined us as Executive Vice President in
August 1995. From January 1995 until it was merged into Titan in March 1999, he
also served as President and Chief Executive Officer of Theracell. From
June 1991 until December 1994, Dr. Allen was Vice President and General Manager
of the Neuroscience Strategic Business Unit of Hoechst-Roussel Pharmaceuticals,
Inc. Dr. Allen holds a Ph.D. in medicinal chemistry and a B.S. in pharmacy from
the Medical College of Virginia.

    ROBERT E. FARRELL joined us as Executive Vice President and Chief Financial
Officer in September 1996. Mr. Farrell was employed by Fresenius USA, Inc. from
1991 until August 1996 where he served in various capacities, including Vice
President Administration, Chief Financial Officer and General Counsel. His last
position was Corporate Group Vice President. Mr. Farrell holds a B.A. from
University of Notre Dame and a J.D. from Hastings College of Law, University of
California.

    VICTOR J. BAUER, PH.D., has served as a director of Titan since
November 1997. Dr. Bauer joined us in February 1997, and currently serves as
Executive Director of Corporate Development. From April 1996 until its merger
into Titan, Dr. Bauer also served as a director and Chairman of Theracell. From
December 1992 until February 1997, Dr. Bauer was a self-employed consultant to
companies in the pharmaceutical and biotechnology industries. Prior to that
time, Dr. Bauer was with Hoechst-Roussel Pharmaceuticals Inc., where he served
as President from 1988 through 1992.

                                       21
<PAGE>
    ERNST-GUNTER AFTING, M.D., PH.D., has served as a director of Titan since
May 1996. Dr. Afting has served as the President of the GSF-National Center for
Environment and Health, a government research center in Germany, since 1995.
From 1984 until 1995, he was employed in various capacities by the Hoechst
Group, serving as Divisional Head of the Pharmaceuticals Division of the Hoechst
Group from 1991 to 1993 and as President and Chief Executive Officer of Roussel
Uclaf (a majority stockholder of Hoechst AG) in Paris from 1993 until 1995.

    EURELIO M. CAVALIER has served as a director of Titan since September 1998.
From 1958 until his retirement in 1994, Mr. Cavalier was employed in various
capacities by Eli Lilly & Co., serving as Vice President Sales from 1976 to 1982
and Group Vice President U.S. Pharmaceutical Business Unit from 1982 to 1993.
Mr. Cavalier currently serves on the Boards of Directors of DataChem, Inc.,
ProSolv, Inc. and St. Vincent Hospital. He serves on the Advisory Board of COR
Therapeutics and Indiana Heart Institute.

    MICHAEL K. HSU has served as a director of Titan since March 1993. He is
currently a General Partner of EndPoint Merchant Group, a merchant bank
specializing in making investments into the healthcare and life science
industries. Mr. Hsu served as Director-Corporate Finance of National Securities
Corp. from November 1995 through April 1998, and from November 1994 through
October 1995 served with Coleman and Company Securities in the same capacity.
Mr. Hsu previously held various executive positions with Steinberg and Lyman
Health Care Company, Ventana Venture Growth Fund, Asian Pacific Venture Group
(Thailand) and D. Blech Life Science Ventures.

    HUBERT HUCKEL, M.D. has served as a director of Titan since October 1995.
From 1964 until his retirement in December 1992, Dr. Huckel served in various
positions with The Hoechst Group. At the time of his retirement, he was Chairman
of the Board of Hoechst-Roussel Pharmaceuticals, Inc., Chairman and President of
Hoechst-Roussel Agri-Vet Company and a member of the Executive Committee of
Hoechst Celanese Corporation. He currently serves on the Board of Directors of
Thermogenesis, Corp. and Gynetics, Inc.

    MARVIN E. JAFFE, M.D. has served as a director of Titan since October 1995.
From 1988 until April 1994, Dr. Jaffe served as President of R.W. Johnson
Pharmaceutical Research Institute where he was responsible for the research and
development activities in support of a number of Johnson & Johnson companies,
including ORTHO-McNeil Pharmaceuticals, ORTHO Biotech and CILAG. From 1970 until
1988, he was Senior Vice President of the Merck Research Laboratories. He
currently serves on the Boards of Directors of Celltech Group, plc,
Immunomedics, Inc., Matrix Pharmaceuticals, Inc., and Vanguard Medica, plc.

    KONRAD M. WEIS, PH.D., has served as a director of Titan since March 1993.
Dr. Weis is the former President and Chief Executive Officer of Bayer
Corporation. Dr. Weis serves as a director of PNC Equity Management Company,
Michael Baker Corporation, Visible Genetics, Inc. and Demegen, Inc.

    Directors serve until the next annual meeting or until their successors are
elected and qualified. Officers serve at the discretion of the Board of
Directors, subject to rights, if any, under contracts of employment. See "Item
11. Executive Compensation--Employment Agreements."

DIRECTOR COMPENSATION

    During 1999, non-employee directors are entitled to receive annual options
to purchase 10,000 shares of common stock vesting quarterly as fees for the
Board of Directors meetings, and are reimbursed for their expenses in attending
such meetings. Directors are not precluded from serving us in any other capacity
and receiving compensation therefor. In addition, directors are entitled to
receive options (Director Options) pursuant to our 1998 Stock Option Plan. In
August 1999, each of our current directors received Director Options to purchase
5,000 shares of common stock at an exercise price of $9.063 per share.

    We are a party to a consulting agreement with Dr. Afting pursuant to which
he receives fees of $7,000 annually.

                                       22
<PAGE>
    We are a party to a consulting agreement with Dr. Jaffe pursuant to which he
receives fees of $35,000 annually.

BOARD COMMITTEES AND DESIGNATED DIRECTORS

    The Board of Directors has an Executive Committee, a Compensation Committee
and an Audit Committee. The Executive Committee exercises all the power and
authority of the Board of Directors in the management of Titan between Board
meetings, to the extent permitted by law. The Compensation Committee makes
recommendations to the Board concerning salaries and incentive compensation for
our officers and employees and administers our stock option plans. The Audit
Committee reviews the results and scope of the audit and other accounting
related matters.

    The Board of Directors met four times during 1999 and also took action by
unanimous written consent. The Executive Committee met one time and also took
action by unanimous written consent, and the Compensation Committee and Audit
Committee each met one time. Each of our current directors attended at least 75%
of the aggregate of (i) the meetings of the Board of Directors and
(ii) meetings of any Committees of the Board on which such person served which
were held during the time such person served.

COMPLIANCE WITH SECTION 16(A) OF THE SECURITIES EXCHANGE ACT OF 1934

    Section 16(a) of the Securities Exchange Act of 1934, as amended, requires
our executive officers, directors and persons who beneficially own more than 10%
of a registered class of our equity securities to file with the Securities and
Exchange Commission initial reports of ownership and reports of changes in
ownership of our common stock and other equity securities. Such executive
officers, directors, and greater than 10% beneficial owners are required by SEC
regulation to furnish us with copies of all Section 16(a) forms filed by such
reporting persons.

    Based solely on our review of such forms furnished to us and written
representations from certain reporting persons, we believe that all filing
requirements applicable to our executive officers, directors and greater than
10% beneficial owners were complied with.

ITEM 11. EXECUTIVE COMPENSATION.

    The following summary compensation table sets forth the aggregate
compensation awarded to, earned by, or paid to the Chief Executive Officer and
to executive officers whose annual compensation exceeded $100,000 for the fiscal
year ended December 31, 1999 (collectively, the "named executive officers") for
services during the fiscal years ended December 31, 1999, 1998 and 1997:

                                       23
<PAGE>
                           SUMMARY COMPENSATION TABLE

<TABLE>
<CAPTION>
                                                                    ANNUAL COMPENSATION
                                                              --------------------------------
NAME AND PRINCIPAL POSITION                                     YEAR      SALARY      BONUS
---------------------------                                   --------   --------   ----------
<S>                                                           <C>        <C>        <C>
Louis R. Bucalo ............................................    1999     $222,013   $     0
  President and Chief Executive Officer                         1998     $243,100   $     0
                                                                1997     $231,525   $58,721(1)
Sunil Bhonsle ..............................................    1999     $180,100   $     0
  Executive Vice President and                                  1998     $194,800   $     0
  Chief Operating Officer                                       1997     $190,991   $68,370(1)
Richard C. Allen ...........................................    1999     $180,475   $     0
  Executive Vice President (2)                                  1998     $197,800   $     0
                                                                1997     $193,984   $77,096(1)
Robert E. Farrell ..........................................    1999     $173,425   $     0
  Executive Vice President and                                  1998     $190,400   $     0
  Chief Financial Officer                                       1997     $186,665   $18,500
</TABLE>

------------------------

(1) Bonuses pertain to fiscal year 1995 and were paid in 1997.

(2) Dr. Allen also served as President and Chief Executive Officer of Theracell
    until Theracell merged with and into Titan in March 1999, and President and
    Chief Operating Officer of ProNeura during these periods. Until March 1999,
    Dr. Allen received his entire salary from Theracell. Dr. Allen's bonus in
    1997 included $20,000 paid by Titan.

                       OPTION GRANTS IN LAST FISCAL YEAR

    The following table contains information concerning the stock option grants
made to the named executive officers during the fiscal year ended December 31,
1999. No stock appreciation rights were granted to these individuals during such
year.

<TABLE>
<CAPTION>
                                                                          INDIVIDUAL GRANT
                                                NUMBER OF    ------------------------------------------
                                                SECURITIES     % OF TOTAL
                                                UNDERLYING   OPTIONS GRANTED   EXERCISE OR
                                                 OPTIONS      TO EMPLOYEES     BASE PRICE    EXPIRATION
NAME                                             GRANTED       FISCAL YEAR     ($/SH) (1)       DATE
----                                            ----------   ---------------   -----------   ----------
<S>                                             <C>          <C>               <C>           <C>
Louis R. Bucalo...............................    71,500          5.35%          $ 3.625     01/04/2009
Louis R. Bucalo...............................    28,000          2.09%          $ 3.688     02/04/2009
Louis R. Bucalo...............................    27,531          2.06%          $ 0.080     03/10/2009
Louis R. Bucalo...............................     5,000          0.37%          $ 9.063     08/30/2009
Louis R. Bucalo...............................   400,000         29.91%          $12.750     11/24/2009
Sunil Bhonsle.................................    55,600          4.16%          $ 3.625     01/04/2009
Sunil Bhonsle.................................    21,000          1.57%          $ 3.688     02/04/2009
Sunil Bhonsle.................................   184,000         13.76%          $12.750     11/24/2009
Richard C. Allen..............................    41,200          3.08%          $ 3.625     01/04/2009
Richard C. Allen..............................    21,000          1.57%          $ 3.688     02/04/2009
Richard C. Allen..............................   132,000          9.87%          $12.750     11/24/2009
Robert E. Farrell.............................    26,300          1.97%          $ 3.625     01/04/2009
Robert E. Farrell.............................    21,000          1.57%          $ 3.688     02/04/2009
Robert E. Farrell.............................    66,000          4.93%          $12.750     11/24/2009
</TABLE>

------------------------

(1) The exercise price may be paid in cash, in shares of common stock valued at
    the fair market value on the exercise date or through a cashless exercise
    procedure involving a same-day sale of the purchase shares. We may also
    finance the option exercise by loaning the optionee sufficient funds to pay
    the

                                       24
<PAGE>
    exercise price for the purchased shares, together with any federal and state
    income tax liability incurred by the optionee in connection with such
    exercise.

AGGREGATE OPTION EXERCISES IN LAST FISCAL YEAR AND FISCAL YEAR-END OPTION VALUES

    The following table sets forth information concerning option exercises and
option holdings for the fiscal year ended December 31, 1999 with respect to the
named executive officers. No stock appreciation rights were exercised during
such year or were outstanding at the end of that year.

<TABLE>
<CAPTION>
                                                    NUMBER OF SECURITIES
                                                   UNDERLYING UNEXERCISED      VALUE OF UNEXERCISED IN-THE-
                                     SHARES           OPTIONS AT FY-END        MONEY OPTIONS AT FY-END (1)
                                    ACQUIRED     ---------------------------   ----------------------------
NAME                               ON EXERCISE   EXERCISABLE   UNEXERCISABLE   EXERCISABLE   UNEXERCISABLE
----                               -----------   -----------   -------------   -----------   --------------
<S>                                <C>           <C>           <C>             <C>           <C>
Louis R. Bucalo..................        -0-       754,130       473,044(2)    $9,937,731    $3,439,758(2)
Sunil Bhonsle....................        -0-       403,678       231,621(2)    $5,590,912    $1,863,912(2)
Richard C. Allen.................        -0-       308,515       153,169(2)    $4,868,737    $1,168,360(2)
Robert E. Farrell................     21,000       170,966        94,234       $2,085,619    $  768,650
</TABLE>

------------------------

(1) Based on the fair market value of our common stock at year-end, $19.000 per
    share, less the exercise price payable for such shares.

(2) A portion of employee's options are immediately exercisable. Upon the
    employee's cessation of service, we have the right to repurchase any shares
    acquired pursuant to said grant. Our right to repurchase shares expires in
    equal monthly installments over the five year period commencing on the date
    of grant. Options to which our repurchase right has not expired are deemed
    unexercisable for purposes of this table.

EMPLOYMENT AGREEMENTS

    We are a party to an employment agreement with Dr. Bucalo expiring in
February 2003 which provides for a base annual salary of $210,000, subject to
annual increases of 5% and bonuses of up to 25% at the discretion of the Board
of Directors. In the event of the termination of the agreement with Dr. Bucalo,
other than for reasons specified therein, we are obligated to make severance
payments equal to his base annual salary for the greater of the balance of the
term of the agreement or 18 months.

    Employment agreements with each of Dr. Allen, Mr. Bhonsle and Mr. Farrell
provide for a base annual salary of $185,000 subject to automatic annual
increases based on increases in the consumer price index, and bonuses of up to
20% at the discretion of the Board of Directors. In the event the employee's
employment is terminated other than for "good cause" (as defined), we are
obligated to make severance payments equal to the base annual salary for six
months. All of the agreements contain confidentiality provisions.

    In order to preserve our cash resources, we have determined, and the
executives agreed, that the 1999 salaries of Drs. Bucalo and Allen and Messrs.
Bhonsle and Farrell would be at $219,000, $178,000, $178,000 and $171,000,
respectively.

ITEM 12. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT.

    The following table sets forth, as of March 24, 2000, certain information
concerning the beneficial ownership of our common stock by (i) each stockholder
known by us to own beneficially five percent or

                                       25
<PAGE>
more of our outstanding common stock; (ii) each director; (iii) each executive
officer; and (iv) all of our executive officers and directors as a group, and
their percentage ownership and voting power.

<TABLE>
<CAPTION>
                                                              SHARES BENEFICIALLY   PERCENT OF SHARES
NAME AND ADDRESS OF BENEFICIAL OWNER (1)                           OWNED (2)        BENEFICIALLY OWNED
----------------------------------------                      -------------------   ------------------
<S>                                                           <C>                   <C>
Louis R. Bucalo, M.D........................................     1,167,685(3)              4.5%
Ernst-Gunter Afting, M.D., Ph.D.............................        24,000(4)                 *
Richard C. Allen, Ph.D......................................       349,108(5)              1.4%
Victor J. Bauer, Ph.D.......................................        65,449(6)                 *
Sunil Bhonsle...............................................       480,249(7)              1.9%
Eurelio M. Cavalier.........................................        12,500(4)                 *
Robert E. Farrell...........................................       200,217(8)                 *
Michael K. Hsu..............................................        52,167(9)                 *
Hubert Huckel, M.D..........................................       136,500(10)                *
Marvin E. Jaffe, M.D........................................        29,661(11)                *
Konrad M. Weis, Ph.D........................................        76,401(12)                *
Lindsay A. Rosenwald, M.D. .................................     1,509,294(13)             5.8%
  787 Seventh Avenue, 48th Floor
  New York, NY 10019
All executive officers and directors as a group                  2,593,937                10.1%
  (11) persons..............................................
</TABLE>

------------------------

*   Less than one percent.

(1) Unless otherwise indicated, the address of such individual is c/o Titan
    Pharmaceuticals, Inc., 400 Oyster Point Boulevard, Suite 505, South San
    Francisco, California 94080.

(2) In computing the number of shares beneficially owned by a person and the
    percentage ownership of a person, shares of our common stock subject to
    options held by that person that are currently exercisable or exercisable
    within 60 days are deemed outstanding. Such shares, however, are not deemed
    outstanding for purposes of computing the percentage ownership of each other
    person. Except as indicated in the footnotes to this table and pursuant to
    applicable community property laws, the persons named in the table have sole
    voting and investment power with respect to all shares of common stock.

(3) Includes 867,454 shares issuable upon exercise of outstanding options.

(4) Represents shares issuable upon exercise of outstanding options.

(5) Includes 344,108 shares issuable upon exercise of outstanding options.

(6) Includes 60,449 shares issuable upon exercise of outstanding options.

(7) Includes 463,249 shares issuable upon exercise of outstanding options.

(8) Includes 169,217 shares issuable upon exercise of outstanding options.

(9) Includes 32,166 shares issuable upon exercise of outstanding options.

(10) Includes 26,500 shares issuable upon exercise of outstanding options.
    Includes 100,000 shares held by a family partnership for which Dr. Huckel
    serves as general partner.

(11) Includes 26,500 shares issuable upon exercise of warrants and outstanding
    options.

(12) Includes 31,617 shares issuable upon exercise of outstanding options.

(13) Includes (i) 45,042 shares held by each of June Street Corporation and
    Huntington Street Corporation, companies wholly-owned by Dr. Rosenwald; (ii)
    580,853 shares held by a fund for which a wholly-owned company of Dr.
    Rosenwald's serves as investment manager; and (iii) an aggregate of

                                       26
<PAGE>
    296,377 shares held by two funds for which the same wholly-owned company
    serves as general partner. Does not include shares owned by Dr. Rosenwald's
    wife and his children's trusts, as to which he disclaims beneficial
    ownership. The foregoing information is derived from a Schedule 13G/A filed
    on behalf of Dr. Rosenwald on February 14, 2000.

ITEM 13. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS.

    In June and July of 1997, Dr. Hubert Huckel, a director of Titan, received
an aggregate of $155,000 in consulting fees for services rendered in connection
with our consummation of the Zomaril (iloperidone) license. Dr. Huckel was paid
pursuant to a consulting agreement which provided for the payment of fees based
upon a percentage of the consideration paid by us upon completion of a licensing
transaction with Dr. Huckel's assistance. The consulting agreement expired by
its terms in January 1998.

    In January 1999, we completed a private placement of 2,254,545 shares of our
common stock. Dr. Hubert Huckel and Mr. Michael Hsu, directors of Titan,
participated in the offering by purchasing 100,000 and 5,272 shares,
respectively.

    We believe that all of the transactions set forth above were made on terms
no less favorable to us than could have been obtained from unaffiliated third
parties. We have adopted a policy that all future transactions, including loans,
between us and our officers, directors, principal stockholders and their
affiliates must be approved by a majority of the Board of Directors, including a
majority of the independent and disinterested outside directors on the Board of
Directors.

                                       27
<PAGE>
                                    PART IV

ITEM 14. EXHIBITS, FINANCIAL STATEMENTS SCHEDULES AND REPORTS ON FORM 8-K

(A) 1.  FINANCIAL STATEMENTS

        An index to Consolidated Financial Statements appears on page F-1.

    2.  SCHEDULES

    All financial statement schedules are omitted because they are not
applicable, not required under the instructions or all the information required
is set forth in the financial statements or notes thereto.

    3.  EXHIBITS

<TABLE>
<CAPTION>

<C>                       <C>        <S>
                    3.1    --        Restated Certificate of Incorporation of the Registrant(1)
                    3.2    --        Form of Amendment to Restated Certificate of Incorporation
                                     of the Registrant(1)
                    3.3    --        By-laws of the Registrant(1)
                    4.4    --        Form of Underwriter's Unit Purchase Option(1)
                    4.5    --        Form of Investor Rights Agreement between the Registrant and
                                     the holders of Series A and Series B Preferred Stock(1)
                    4.6    --        Form of Placement Agent's Unit Purchase Option(4)
                    4.7    --        Certificate of Designation of Series C Preferred Stock(8)
                   10.1    --        1993 Stock Option Plan(1)
                   10.2    --        1995 Stock Option Plan(1)
                   10.3    --        Employment Agreement between the Registrant and Louis Bucalo
                                     dated February 1, 1993, amended as of February 3, 1994(1)
                   10.4    --        Employment Agreement between Registrant and Richard Allen
                                     dated July 28, 1995(1)
                   10.5    --        Employment Agreement between Registrant and Sunil Bhonsle,
                                     dated August 6, 1995(1)
                   10.6    --        Form of Indemnification Agreement(1)
                  +10.9    --        MDR Exclusive License Agreement between Ingenex, Inc.
                                     (formerly Pharm-Gen Systems Ltd.) and the Board of Trustees
                                     of the University of Illinois dated May 6, 1992(1)
                 +10.11    --        License Agreement between Theracell, Inc. and New York
                                     University dated November 20, 1992, as amended as of
                                     February 23, 1993 and as of February 25, 1995(1)
                 +10.12    --        License Agreement between the Registrant and the
                                     Massachusetts Institute of Technology dated September 28,
                                     1995(1)
                 +10.14    --        Exclusive License Agreement between Ingenex, Inc. and the
                                     Board of Trustees of the University of Illinois, dated
                                     July 1, 1994(1)
                 +10.15    --        Exclusive License Agreement between Ingenex, Inc. and the
                                     Board of Trustees of the University of Illinois, dated
                                     July 1, 1994(1)
                 +10.16    --        License Agreement between Ingenex, Inc. and the
                                     Massachusetts Institute of Technology, dated September 11,1
                                     992(1)
                 +10.17    --        License Agreement between Ingenex, Inc. and Baylor College
                                     of Medicine, dated October 21, 1992(1)
                  10.18    --        Lease for Registrant's facilities(2)
                 +10.19    --        License Agreement between Theracell, Inc. and the University
                                     of South Florida dated March 15, 1996(3)
                 +10.20    --        License Agreement between Trilex Pharmaceuticals, Inc.
                                     (formerly Ascalon Pharmaceuticals, Inc.) and the University
                                     of Kentucky Research Foundation dated May 30, 1996(4)
                 +10.22    --        License Agreement between the Registrant and Hoechst Marion
                                     Roussel, Inc. effective as of December 31, 1996(5)
</TABLE>

                                       28
<PAGE>
<TABLE>
<C>                       <C>        <S>
                  10.23    --        Employment Agreement between Registrant and Robert E.
                                     Farrell dated August 9, 1996(5)
                  10.24    --        Financing Agreement between the Registrant and Ansan
                                     Pharmaceuticals, Inc. dated March 21, 1997(6)
                  10.25    --        Agreement for Purchase and Sale of Assets between the
                                     Registrant and Pharmaceuticals Product Development, Inc.
                                     dated June 4, 1997(6)
                 +10.27    --        License Agreement between the Registrant and Bar-Ilan
                                     Research and Development Company Limited effective
                                     November 25, 1997(7)
                  10.28    --        License Agreement between the Registrant and Ansan
                                     Pharmaceuticals, Inc. dated November 24, 1997(7)
                  10.29    --        Stock Purchase Agreement between the Registrant and Ansan
                                     Pharmaceuticals, Inc. effective November 25, 1997(7)
                 +10.30    --        Sublicense Agreement between the Registrant and Novartis
                                     Pharma AG dated November 20, 1997(7)
                  10.31    --        1998 Stock Option Plan(9)
                ++10.32    --        License Agreement between the Registrant and Schering AG
                                     dated January 25, 2000.
                   23.2    --        Consent of Ernst & Young LLP, Independent Auditors.
                   27.1    --        Financial Data Schedule.
</TABLE>

------------------------

+   Confidential treatment has been granted with respect to portions of this
    exhibit.

++  Confidential treatment has been requested with respect to portions of this
    exhibit.

(1) Incorporated by reference from the Registrant's Registration Statement on
    Form SB-2 (File No. 33-99386).

(2) Incorporated by reference from the Registrant's Annual Report on
    Form 10-KSB for the year ended December 31, 1995.

(3) Incorporated by reference from the Registrant's Quarterly Report on Form
    10-QSB for the period ended March 31, 1996.

(4) Incorporated by reference from the Registrant's Registration Statement on
    Form SB-2 (File No. 333-13469).

(5) Incorporated by reference from the Registrant's Annual Report on
    Form 10-KSB for the year ended December 31, 1996.

(6) Incorporated by reference from the Registrant's Quarterly Report on Form
    10-QSB for the period ended March 31, 1997.

(7) Incorporated by reference from the Registrant's Registration Statement on
    Form S-3 (File No. 333-42367).

(8) Incorporated by reference from the Registrant's Annual Report on Form 10-K
    for the year ended December 31, 1997.

(9) Incorporated by reference from the Registrant's Annual Report on Form 10-K
    for the year ended December 31, 1998.

(B) REPORTS ON FORM 8-K

    On October 19, 1999, we filed a current report on Form 8-K to call for
redemption of our outstanding Class A warrants. On December 3, 1999, we filed
another current report on Form 8-K to announce the results of the warrant call.

                                       29
<PAGE>
                          TITAN PHARMACEUTICALS, INC.
                         (A DEVELOPMENT STAGE COMPANY)

                   INDEX TO CONSOLIDATED FINANCIAL STATEMENTS

<TABLE>
<CAPTION>
                                                                PAGE
                                                              --------
<S>                                                           <C>
Report of Ernst & Young LLP, Independent Auditors...........     F-2

Consolidated Financial Statements

  Consolidated Balance Sheets...............................     F-3

  Consolidated Statements of Operations.....................     F-4

  Consolidated Statement of Stockholders' Equity............     F-5

  Consolidated Statements of Cash Flows.....................     F-8

  Notes to Consolidated Financial Statements................     F-9
</TABLE>

                                      F-1
<PAGE>
               REPORT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS

The Board of Directors and Stockholders
Titan Pharmaceuticals, Inc.

    We have audited the accompanying consolidated balance sheets of Titan
Pharmaceuticals, Inc. (a development stage company) as of December 31, 1999 and
1998, and the related consolidated statements of operations, stockholders'
equity, and cash flows for each of the three years in the period ended December
31, 1999 and for the period from July 25, 1991 (commencement of operations) to
December 31, 1999. These financial statements are the responsibility of the
Company's management. Our responsibility is to express an opinion on these
financial statements based on our audits.

    We conducted our audits in accordance with generally accepted auditing
standards. Those standards require that we plan and perform the audit to obtain
reasonable assurance about whether the financial statements are free of material
misstatement. An audit includes examining, on a test basis, evidence supporting
the amounts and disclosures in the financial statements. An audit also includes
assessing the accounting principles used and significant estimates made by
management, as well as evaluating the overall financial statement presentation.
We believe that our audits provide a reasonable basis for our opinion.

    In our opinion, the financial statements referred to above present fairly,
in all material respects, the consolidated financial position of Titan
Pharmaceuticals, Inc. (a development stage company) at December 31, 1999 and
1998, and the consolidated results of its operations and its cash flows for each
of the three years in the period ended December 31, 1999 and for the period from
July 25, 1991 (commencement of operations) to December 31, 1999, in conformity
with accounting principles generally accepted in the United States.

                                        /s/ Ernst & Young LLP

Palo Alto, California
February 24, 2000
except for Note 14, as to which the date is
March 3, 2000

                                      F-2
<PAGE>
                          TITAN PHARMACEUTICALS, INC.
                         (A DEVELOPMENT STAGE COMPANY)

                          CONSOLIDATED BALANCE SHEETS

<TABLE>
<CAPTION>
                                                                     DECEMBER 31,
                                                              ---------------------------
                                                                  1999           1998
                                                              ------------   ------------
<S>                                                           <C>            <C>
ASSETS

Current assets:
  Cash and cash equivalents.................................  $ 46,454,129   $ 11,654,896
  License fees and grants receivable........................       149,778             --
  Prepaid expenses and other current assets.................       327,218        139,958
                                                              ------------   ------------
    Total current assets....................................    46,931,125     11,794,854
Furniture and equipment, net................................       414,823        416,956
Other assets................................................        15,958         15,783
                                                              ------------   ------------
                                                              $ 47,361,906   $ 12,227,593
                                                              ============   ============

LIABILITIES AND STOCKHOLDERS' EQUITY

Current liabilities:
  Accounts payable..........................................  $    848,546   $    410,235
  Accrued clinical trials expenses..........................       437,572        653,218
  Accrued compensation and related expenses.................       177,214        182,647
  Accrued professional fees and other liabilities...........       355,641        334,123
                                                              ------------   ------------
    Total current liabilities...............................     1,818,973      1,580,223
Commitments
Minority interest--Series B preferred stock of Ingenex,
Inc.........................................................     1,241,032      1,241,032
Stockholders' Equity
  Preferred stock, $0.001 par value per share; 5,000,000
    shares authorized, issuable in series:
    Convertible Series C, 222,400 shares designated, 222,400
      shares issued and outstanding, with an aggregate
      liquidation value of $2,224, at December 31, 1999 and
      1998..................................................            --             --
    Convertible Series D, 606,061 shares designated, 606,061
      shares issued and outstanding, with an aggregate
      liquidation value of $30,303, at December 31, 1999 and
      1998..................................................     5,000,000      5,000,000
  Common stock, $0.001 par value per share; 50,000,000
    shares authorized at December 31, 1999 and 1998;
    22,891,912 and 13,123,508 shares issued and outstanding
    at December 31, 1999 and 1998, respectively.............    98,696,741     52,291,369
  Additional paid-in capital................................     6,524,247      6,524,204
  Deferred compensation.....................................      (500,895)      (286,580)
  Deficit accumulated during developmental stage............   (65,418,192)   (54,122,655)
                                                              ------------   ------------
    Total Stockholders' equity..............................    44,301,901      9,406,338
                                                              ------------   ------------
                                                              $ 47,361,906   $ 12,227,593
                                                              ============   ============
</TABLE>

                            See accompanying notes.

                                      F-3
<PAGE>
                          TITAN PHARMACEUTICALS, INC.
                         (A DEVELOPMENT STAGE COMPANY)

                     CONSOLIDATED STATEMENTS OF OPERATIONS

<TABLE>
<CAPTION>
                                                                                       PERIOD FROM
                                                                                       COMMENCEMENT
                                                                                      OF OPERATIONS
                                                YEAR ENDED DECEMBER 31,             (JULY 25, 1991) TO
                                       ------------------------------------------      DECEMBER 31,
                                           1999           1998           1997              1999
                                       ------------   ------------   ------------   ------------------
<S>                                    <C>            <C>            <C>            <C>
License and grant revenue............  $    337,254   $         --   $ 17,499,948      $ 18,235,535

Operating expenses:
  Research and development...........     9,428,550      7,813,363      9,309,923        54,132,229
  Acquired in-process research and
    development......................       135,785             --      9,500,000        10,321,785
  General and administrative.........     2,794,682      3,707,874      6,513,603        24,844,505
                                       ------------   ------------   ------------      ------------
    Total operating expenses.........    12,359,017     11,521,237     25,323,526        89,298,519
                                       ------------   ------------   ------------      ------------
    Loss from operations.............   (12,021,763)   (11,521,237)    (7,823,578)      (71,062,984)

Other income (expense):
  Equity in loss of Ansan
    Pharmaceuticals, Inc.............            --             --       (590,853)       (2,046,939)
  Gain on sale of technology.........            --             --      8,361,220         8,361,220
  Interest income....................       755,777        847,581        666,419         3,440,519
  Interest expense...................            --           (215)      (226,685)       (4,389,902)
  Other (expense) income.............       (29,551)        59,507        205,024           234,980
                                       ------------   ------------   ------------      ------------
    Other income, net................       726,226        906,873      8,415,125         5,599,878
                                       ------------   ------------   ------------      ------------
(Loss) income before minority
  interest...........................   (11,295,537)   (10,614,364)       591,547       (65,463,106)

Minority interest in losses of
  subsidiaries.......................            --             --             64            44,914
                                       ------------   ------------   ------------      ------------
Net (loss) income....................   (11,295,537)   (10,614,364)       591,611       (65,418,192)

Deemed dividend upon conversion of
  preferred stock....................            --             --             --        (5,431,871)
                                       ------------   ------------   ------------      ------------
Net (loss) income attributable to
  common Stockholders................  $(11,295,537)  $(10,614,364)  $    591,611      $(70,850,063)
                                       ============   ============   ============      ============
Net (loss) income per common share:
  Basic..............................  $      (0.70)  $      (0.81)  $       0.05
                                       ============   ============   ============
  Diluted............................  $      (0.70)  $      (0.81)  $       0.04
                                       ============   ============   ============
Weighted average shares used in
  computing net (loss) income per
  common share:
  Basic..............................    16,112,260     13,108,512     13,002,050
                                       ============   ============   ============
  Diluted............................    16,112,260     13,108,512     13,476,644
                                       ============   ============   ============
</TABLE>

                            See accompanying notes.

                                      F-4
<PAGE>
                          TITAN PHARMACEUTICALS, INC.
                         (A DEVELOPMENT STAGE COMPANY)
                 CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY
<TABLE>
<CAPTION>
                                             PREFERRED                   COMMON
                                               STOCK                     STOCK           ADDITIONAL
                                     --------------------------   --------------------    PAID-IN       DEFERRED      ACCUMULATED
                                       SHARES         AMOUNT       SHARES      AMOUNT     CAPITAL     COMPENSATION      DEFICIT
                                     -----------   ------------   ---------   --------   ----------   -------------   ------------
<S>                                  <C>           <C>            <C>         <C>        <C>          <C>             <C>
Net loss--Commencement of
  operations (July 25, 1991) to
  December 31, 1992................           --   $         --          --   $     --   $      --      $      --     $  (819,331)
Issuance of common stock to
  founders and investors...........                               1,183,361     58,575
Issuance of common stock to
  employees........................                                 210,232        813
Issuance of Series A preferred
  stock, net.......................    3,278,069     16,457,649
Forgiveness of notes payable.......                                                         40,000
Net loss...........................                                                                                    (5,757,296)
                                     -----------   ------------   ---------   --------   ----------     ---------     ------------
Balances at December 31, 1993......    3,278,069     16,457,649   1,393,593     59,388      40,000             --      (6,576,627)
Issuance of common stock to a
  consultant.......................                                  14,926         88
Increase in paid-in capital from
  issuance of common stock by
  Ingenex, Inc.....................                                                        128,805
Net loss...........................                                                                                   (12,974,175)
                                     -----------   ------------   ---------   --------   ----------     ---------     ------------
Balances at December 31, 1994......    3,278,069     16,457,649   1,408,519     59,476     168,805             --     (19,550,802)
Issuance of Series B preferred
  stock, net.......................      244,043      1,143,794
Increase in paid-in capital from
  issuance of warrants by Ingenex,
  Inc. in connection with bridge
  financing........................                                                        600,000
Increase in paid-in capital from
  issuance of warrants by Titan
  Pharmaceuticals, Inc. in
  connection with bridge
  financing........................                                                      1,200,000
Conversion of related parties notes
  payable and accrued interest into
  Series A preferred stock.........      256,130      1,306,329
Increase in paid-in capital from
  issuance of common stock by Ansan
  Pharmaceuticals, Inc.............                                                      3,777,548
Deferred compensation related to
  stock options, net of
  amortization.....................                                                        440,000       (418,000)
Issuance of common stock to acquire
  minority interest of Theracell,
  Inc..............................                                 140,000    686,000
Net loss...........................                                                                                   (11,693,454)
                                     -----------   ------------   ---------   --------   ----------     ---------     ------------
Balances at December 31, 1995......    3,778,242     18,907,772   1,548,519    745,476   6,186,353       (418,000)    (31,244,256)

<CAPTION>

                                         TOTAL
                                     STOCKHOLDERS'
                                        EQUITY
                                     -------------
<S>                                  <C>
Net loss--Commencement of
  operations (July 25, 1991) to
  December 31, 1992................  $   (819,331)
Issuance of common stock to
  founders and investors...........        58,575
Issuance of common stock to
  employees........................           813
Issuance of Series A preferred
  stock, net.......................    16,457,649
Forgiveness of notes payable.......        40,000
Net loss...........................    (5,757,296)
                                     ------------
Balances at December 31, 1993......     9,980,410
Issuance of common stock to a
  consultant.......................            88
Increase in paid-in capital from
  issuance of common stock by
  Ingenex, Inc.....................       128,805
Net loss...........................   (12,974,175)
                                     ------------
Balances at December 31, 1994......    (2,864,872)
Issuance of Series B preferred
  stock, net.......................     1,143,794
Increase in paid-in capital from
  issuance of warrants by Ingenex,
  Inc. in connection with bridge
  financing........................       600,000
Increase in paid-in capital from
  issuance of warrants by Titan
  Pharmaceuticals, Inc. in
  connection with bridge
  financing........................     1,200,000
Conversion of related parties notes
  payable and accrued interest into
  Series A preferred stock.........     1,306,329
Increase in paid-in capital from
  issuance of common stock by Ansan
  Pharmaceuticals, Inc.............     3,777,548
Deferred compensation related to
  stock options, net of
  amortization.....................        22,000
Issuance of common stock to acquire
  minority interest of Theracell,
  Inc..............................       686,000
Net loss...........................   (11,693,454)
                                     ------------
Balances at December 31, 1995......    (5,822,655)
</TABLE>

                            See accompanying notes.

                                      F-5
<PAGE>
                          TITAN PHARMACEUTICALS, INC.
                         (A DEVELOPMENT STAGE COMPANY)
           CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY (CONTINUED)
<TABLE>
<CAPTION>
                                             PREFERRED                    COMMON
                                               STOCK                      STOCK             ADDITIONAL
                                     -------------------------   ------------------------    PAID-IN       DEFERRED
                                       SHARES        AMOUNT        SHARES       AMOUNT       CAPITAL     COMPENSATION
                                     ----------   ------------   ----------   -----------   ----------   -------------
<S>                                  <C>          <C>            <C>          <C>           <C>          <C>
Balances at December 31, 1995......   3,778,242     18,907,772    1,548,519       745,476   6,186,353       (418,000)
Issuance of common stock in an
  initial public offering, net.....                               3,680,000    15,850,357
Conversion of Series A & Series B
  preferred stock to common as a
  result of the initial public
  offering.........................  (3,778,242)   (18,907,772)   5,521,140    18,907,772
Issuance of common stock upon
  exercise of stock options........                                  16,520        10,664
Issuance of common stock in a
  private placement, net...........                               1,536,000    13,739,628
Deferred compensation related to
  stock options....................                                                           335,000       (335,000)
Issuance of common stock upon
  exercise of Class A Warrants.....                                  59,014       365,887
Issuance of common stock upon
  exercise of placement agent
  warrants.........................                                  37,844            --
Amortization of deferred
  compensation.....................                                                                          122,900
Net loss...........................
                                     ----------   ------------   ----------   -----------   ----------     ---------
Balances at December 31, 1996......          --             --   12,399,037    49,619,784   6,521,353       (630,100)
Issuance of common stock in partial
  consideration for a technology
  license..........................                                 594,595            --
Issuance of common stock upon
  exercise of placement agent
  warrants.........................                                  53,765            --
Issuance of common stock upon
  exercise of stock options........                                   5,117         3,012
Issuance of Series C preferred
  stock in connection with the
  liquidation and merger of Trilex,
  Inc..............................     222,400             --
Issuance of Series D preferred
  stock............................     606,061      5,000,000
Amortization of deferred
  compensation.....................                                                                          171,760
Net income.........................
                                     ----------   ------------   ----------   -----------   ----------     ---------
Balances at December 31, 1997......     828,461      5,000,000   13,052,514    49,622,796   6,521,353       (458,340)

<CAPTION>

                                                        TOTAL
                                     ACCUMULATED    STOCKHOLDERS'
                                       DEFICIT         EQUITY
                                     ------------   -------------
<S>                                  <C>            <C>
Balances at December 31, 1995......  (31,244,256)     (5,822,655)
Issuance of common stock in an
  initial public offering, net.....                   15,850,357
Conversion of Series A & Series B
  preferred stock to common as a
  result of the initial public
  offering.........................                           --
Issuance of common stock upon
  exercise of stock options........                       10,664
Issuance of common stock in a
  private placement, net...........                   13,739,628
Deferred compensation related to
  stock options....................                           --
Issuance of common stock upon
  exercise of Class A Warrants.....                      365,887
Issuance of common stock upon
  exercise of placement agent
  warrants.........................                           --
Amortization of deferred
  compensation.....................                      122,900
Net loss...........................  (12,855,646)    (12,855,646)
                                     ------------   ------------
Balances at December 31, 1996......  (44,099,902)     11,411,135
Issuance of common stock in partial
  consideration for a technology
  license..........................                           --
Issuance of common stock upon
  exercise of placement agent
  warrants.........................                           --
Issuance of common stock upon
  exercise of stock options........                        3,012
Issuance of Series C preferred
  stock in connection with the
  liquidation and merger of Trilex,
  Inc..............................                           --
Issuance of Series D preferred
  stock............................                    5,000,000
Amortization of deferred
  compensation.....................                      171,760
Net income.........................      591,611         591,611
                                     ------------   ------------
Balances at December 31, 1997......  (43,508,291)     17,177,518
</TABLE>

                            See accompanying notes.

                                      F-6
<PAGE>
                          TITAN PHARMACEUTICALS, INC.
                         (A DEVELOPMENT STAGE COMPANY)
           CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY (CONTINUED)
<TABLE>
<CAPTION>
                                           PREFERRED                  COMMON
                                             STOCK                    STOCK             ADDITIONAL
                                     ---------------------   ------------------------    PAID-IN       DEFERRED      ACCUMULATED
                                      SHARES      AMOUNT       SHARES       AMOUNT       CAPITAL     COMPENSATION      DEFICIT
                                     --------   ----------   ----------   -----------   ----------   -------------   ------------
<S>                                  <C>        <C>          <C>          <C>           <C>          <C>             <C>
Balances at December 31, 1997......  828,461     5,000,000   13,052,514    49,622,796   6,521,353       (458,340)    (43,508,291)
Issuance of common stock upon
  exercise of stock options........                              70,994       212,982
Release of guaranteed security
  value............................                                  --     2,455,591
Increase in paid-in capital from
  issuance of common stock by
  Theracell, Inc...................                                                         2,851
Amortization of deferred
  compensation.....................                                                                      171,760
Net loss...........................                                                                                  (10,614,364)
                                     -------    ----------   ----------   -----------   ----------     ---------     ------------
Balances at December 31, 1998......  828,461    $5,000,000   13,123,508   $52,291,369   $6,524,204     $(286,580)    $(54,122,655)
Issuance of common stock in a
  private placement, net...........                           2,254,545     5,797,159
Increase in paid-in capital from
  issuance of common stock by
  Theracell, Inc...................                                                            43
Issuance of common stock to
  minority stockholders pursuant to
  the Theracell Merger.............                              33,418       135,785
Issuance of common stock upon
  exercise of stock options........                             147,225       468,001
Issuance of common stock upon
  exercise of Class A Warrants,
  net..............................                           7,083,711    39,391,635
Issuance of common stock upon
  exercise of placement agent
  warrants.........................                             125,056            --
Issuance of common stock upon
  exercise of Unit Purchase
  Options..........................                             124,449       181,917
Deferred compensation related to
  stock options....................                                           430,875                   (430,875)
Amortization of deferred
  compensation.....................                                                                      216,560
Net loss...........................                                                                                  (11,295,537)
                                     -------    ----------   ----------   -----------   ----------     ---------     ------------
Balances at December 31, 1999......  828,461    $5,000,000   22,891,912   $98,696,741   $6,524,247     $(500,895)    $(65,418,192)
                                     =======    ==========   ==========   ===========   ==========     =========     ============

<CAPTION>

                                         TOTAL
                                     STOCKHOLDERS'
                                        EQUITY
                                     -------------
<S>                                  <C>
Balances at December 31, 1997......    17,177,518
Issuance of common stock upon
  exercise of stock options........       212,982
Release of guaranteed security
  value............................     2,455,591
Increase in paid-in capital from
  issuance of common stock by
  Theracell, Inc...................         2,851
Amortization of deferred
  compensation.....................       171,760
Net loss...........................   (10,614,364)
                                     ------------
Balances at December 31, 1998......  $  9,406,338
Issuance of common stock in a
  private placement, net...........     5,797,159
Increase in paid-in capital from
  issuance of common stock by
  Theracell, Inc...................            43
Issuance of common stock to
  minority stockholders pursuant to
  the Theracell Merger.............       135,785
Issuance of common stock upon
  exercise of stock options........       468,001
Issuance of common stock upon
  exercise of Class A Warrants,
  net..............................    39,391,635
Issuance of common stock upon
  exercise of placement agent
  warrants.........................            --
Issuance of common stock upon
  exercise of Unit Purchase
  Options..........................       181,917
Deferred compensation related to
  stock options....................            --
Amortization of deferred
  compensation.....................       216,560
Net loss...........................   (11,295,537)
                                     ------------
Balances at December 31, 1999......  $ 44,301,901
                                     ============
</TABLE>

                            See accompanying notes.

                                      F-7
<PAGE>
                          TITAN PHARMACEUTICALS, INC.
                         (A DEVELOPMENT STAGE COMPANY)

                     CONSOLIDATED STATEMENTS OF CASH FLOWS

<TABLE>
<CAPTION>
                                                                                                             PERIOD FROM
                                                                                                             COMMENCEMENT
                                                                                                            OF OPERATIONS
                                                                       YEAR ENDED DECEMBER 31,            (JULY 25, 1991) TO
                                                              -----------------------------------------      DECEMBER 31,
                                                                  1999           1998          1997              1999
                                                              ------------   ------------   -----------   ------------------
<S>                                                           <C>            <C>            <C>           <C>
CASH FLOWS FROM OPERATING ACTIVITIES:
Net (loss) income...........................................  $(11,295,537)  $(10,614,364)  $   591,611      $(65,418,192)
Adjustments to reconcile net (loss) income to net cash
  provided by (used in) operating activities:
  Depreciation and amortization.............................       390,286        293,610       385,503         2,528,041
  Issuance of common stock to acquire in-process
    technology..............................................            --             --     5,500,000         5,500,000
  Payment of guaranteed security value......................            --     (3,044,409)           --        (3,044,409)
  Loss (gain) on sale of assets.............................        13,411         13,016      (216,699)         (190,272)
  Accretion of discount on indebtedness.....................            --             --            --         2,290,910
  Equity in loss of Ansan Pharmaceuticals, Inc..............            --             --       590,854         2,046,940
  Other.....................................................            --             --            --           (35,653)
  Issuance of common stock to acquire minority interest of
    Theracell, Inc..........................................       135,785             --            --           821,785
Changes in operating assets and liabilities:
  Prepaid expenses, other receivables and assets............      (337,213)       297,887       (60,474)         (492,954)
  Receivable--Ansan Pharmaceuticals, Inc....................            --             --       117,881                --
  Accounts payable..........................................       438,311       (405,214)      212,467           848,546
  Other accrued liabilities.................................      (199,561)       309,764      (214,525)          970,427
                                                              ------------   ------------   -----------      ------------
Net cash provided by (used in) operating activities.........   (10,854,518)   (13,149,710)    6,906,618       (54,174,831)
                                                              ------------   ------------   -----------      ------------
CASH FLOWS FROM INVESTING ACTIVITIES:
  Purchase of furniture and equipment, net..................      (185,004)      (298,099)      (78,864)       (1,315,101)
  Purchases of short-term investments.......................            --             --      (100,000)      (59,782,493)
  Proceeds from sales of short-term investments.............            --        500,000    12,600,000        59,782,493
  Other.....................................................            --             --            --          (135,934)
                                                              ------------   ------------   -----------      ------------
Net cash provided by (used in) investing activities.........      (185,004)       201,901    12,421,136        (1,451,035)
                                                              ------------   ------------   -----------      ------------
CASH FLOWS FROM FINANCING ACTIVITIES:
  Issuance of common stock..................................    45,838,712        212,982         3,012        76,080,468
  Deferred financing costs..................................            --             --        96,349          (713,899)
  Issuance of preferred stock...............................            --             --     5,000,000        22,601,443
  Proceeds from debt obligations............................            --             --            --        11,356,500
  Repayment of debt obligations.............................            --             --    (1,289,313)       (8,691,500)
  Proceeds from capital lease bridge financing..............            --             --            --           658,206
  Payments of principal under capital lease obligation......            --             --      (127,462)         (633,766)
  Minority interest.........................................            --             --            --         1,241,032
  Issuance of common stock by subsidiaries..................            43          2,851            --           176,546
                                                              ------------   ------------   -----------      ------------
Net cash provided by financing activities...................    45,838,755        215,833     3,682,586       102,075,030
                                                              ------------   ------------   -----------      ------------
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS........    34,799,233    (12,731,976)   23,010,340        46,454,129
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD............    11,654,896     24,386,872     1,376,532                --
                                                              ------------   ------------   -----------      ------------
CASH AND CASH EQUIVALENTS AT END OF PERIOD..................  $ 46,454,129   $ 11,654,896   $24,386,872      $ 46,454,129
                                                              ============   ============   ===========      ============
SUPPLEMENTAL CASH FLOW DISCLOSURE
Interest paid...............................................  $         --   $        215   $   226,685      $  1,393,524
                                                              ============   ============   ===========      ============
Conversion of related parties notes payable and accrued
  interest into Series A preferred stock....................  $         --   $         --   $        --      $  1,306,329
                                                              ============   ============   ===========      ============
Acquisition of furniture and equipment pursuant to capital
  lease.....................................................  $         --   $         --   $        --      $    595,236
                                                              ============   ============   ===========      ============
</TABLE>

                            See accompanying notes.

                                      F-8
<PAGE>
                          TITAN PHARMACEUTICALS, INC.
                         (A DEVELOPMENT STAGE COMPANY)

                   NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

1.  ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

    THE COMPANY AND ITS SUBSIDIARIES

    We are a biopharmaceutical company developing proprietary therapeutics for
the treatment of central nervous system disorders, cancer, and other serious and
life threatening diseases. We conduct a portion of our operations through our
two subsidiaries: Ingenex, Inc. and ProNeura, Inc. Another subsidiary, Trilex
Pharmaceuticals, Inc., engaged in the development of cancer therapeutic vaccines
utilizing anti-idiotypic antibody technology, was merged with and into Titan in
August 1997 (the Trilex Merger). Theracell, Inc., a majority owned subsidiary
engaged in the development of novel treatments for various neurologic disorders
through the transplantation of neural cells directly into the brain, was merged
with and into Titan in March 1999 (the Theracell Merger). Pursuant to the
Theracell Merger, we issued 33,418 shares of our common stock to the minority
stockholders of Theracell and recorded an in-process research and development
expense of $135,785 which equals the value of the common stock issued. We
operate in one business segment.

    INGENEX, INC.

    Ingenex is engaged in the development of gene-based therapeutics for the
treatment of cancer. In September 1994, Ingenex issued shares of its Series B
convertible preferred stock to a third party for $1,241,032, net of issuance
costs. In June 1997, Ingenex sold a research technology and certain fixed assets
for $8,722,500 in cash and the assumption of certain capital lease liabilities
and recognized a gain of $8,361,220. At December 31, 1999, we owned 81% of
Ingenex, assuming the conversion of all preferred stock to common stock.

    PRONEURA, INC.

    ProNeura was incorporated in October 1995 to engage in the development of
cost effective, long-term treatment solutions to neurologic and psychiatric
disorders through an implantable drug delivery system. At December 31, 1999, we
owned 79% of ProNeura.

    BASIS OF PRESENTATION

    The accompanying consolidated financial statements include the accounts of
Titan and our majority owned subsidiaries. All significant intercompany balances
and transactions are eliminated.

    Since inception, we have devoted substantially all of our resources to
product and technology development, clinical research, raising capital, and
securing patent protection. Accordingly, we are considered to be in the
development stage. We have incurred losses since inception of $65,418,192 and
expect to incur losses, and require additional financial resources to achieve
commercialization of our products.

    USE OF ESTIMATES

    The preparation of financial statements in conformity with generally
accepted accounting principles requires management to make estimates and
assumptions that affect the amounts reported in the financial statements and
accompanying notes. Actual results could differ from those estimates.

                                      F-9
<PAGE>
                          TITAN PHARMACEUTICALS, INC.
                         (A DEVELOPMENT STAGE COMPANY)

             NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

1.  ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (CONTINUED)
    CASH AND CASH EQUIVALENTS

    All highly liquid investments with original maturities of generally three
months or less are considered to be cash equivalents. Cash equivalents include
$46,176,031 and $10,505,429 in money market funds at December 31, 1999 and 1998,
respectively. Money market funds invest primarily in securities with minimal
interest rate risks and generally seek to maintain a constant $1.00 per share
net asset value.

    FURNITURE AND EQUIPMENT

    Furniture and equipment are recorded at cost and depreciated using the
straight-line method over the estimated useful lives of the assets ranging from
three to five years.

    REVENUE RECOGNITION

    License revenue is recognized ratably over the terms of the related license
agreements. Nonrefundable license fees, under which we have no future
performance obligations, are recognized upon receipt (see Note 11). Government
grants which support our research effort in specific projects generally provide
for reimbursement of approved costs as defined in the grant documents, and
revenue is recognized when subsidized project costs are incurred.

    SPONSORED RESEARCH COSTS

    Research and development expenses under sponsored research arrangements are
recorded when related services are performed, generally ratably over the period
of the service agreements. License fees are expensed when paid, if we have no
alternative future use of the technology.

    NET (LOSS) INCOME PER SHARE

    We calculate basic net loss per share using the weighted average common
shares outstanding for the period. Diluted net income per share also includes
the impact of other dilutive equity instruments, primarily preferred stock,
options and warrants. For the years ended December 31, 1999 and 1998, we
reported net losses and, therefore, other dilutive securities were not included
since such inclusion would have been anti-dilutive. Had we been in a net income
position, shares used in calculating diluted earnings per share for 1999 and
1998 would have included the effect of an additional 4,293,859 and 12,387,331
shares, respectively, related to our convertible preferred stock, options and
warrants.

                                      F-10
<PAGE>
                          TITAN PHARMACEUTICALS, INC.
                         (A DEVELOPMENT STAGE COMPANY)

             NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

1.  ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (CONTINUED)
    For the year ended December 31, 1997, we reported net income and, therefore,
all potentially dilutive securities, with exercise prices less than the average
market price of our common stock for the year, have been included in the
calculation, as follows:

<TABLE>
<CAPTION>
                                                                 1997
                                                              ----------
<S>                                                           <C>
Weighted-average shares of common stock outstanding during
  the period................................................  13,002,050

Effect of dilutive securities:
  -  Employee stock options.................................     284,951
  -  Unit purchase options..................................      20,615
  -  Convertible preferred stock............................     104,110
  -  Warrants...............................................      64,918
                                                              ----------
Potentially dilutive securities.............................     474,594
                                                              ----------

Shares used in computation of diluted earnings per share....  13,476,644
                                                              ==========
</TABLE>

    Potentially dilutive securities not included in the computation of diluted
earnings per share for the year ended December 31, 1997 were:

    - Options to purchase 1,066,799 shares of common stock at exercise prices
      greater than the average market price of our common stock and, therefore,
      the effect would have been anti-dilutive.

    - Options to purchase 307,200 Units (one share of common stock and one
      Class A warrant) at $10.42 per unit, which was greater than the average
      market price of our common stock and, therefore, the effect would have
      been anti-dilutive.

    - Warrants to purchase 7,031,986 shares of common stock at $6.20 per share,
      which was greater than the average market price of our common stock and,
      therefore, the effect would have been anti-dilutive.

    - 222,400 shares of Series C convertible preferred stock (the Series C
      Preferred) as the milestones had not been met (see Note 6).

    COMPREHENSIVE INCOME (LOSS)

    Comprehensive income is comprised of net income and other comprehensive
income. Other comprehensive income includes certain changes in equity that are
excluded from net income (loss), such as unrealized gains and losses on
investments. Comprehensive loss was the same as our net loss for the years ended
December 31, 1999, 1998 and 1997.

    RECENT ACCOUNTING PRONOUNCEMENTS

    In June 1998, the Financial Accounting Standards Board issued SFAS No. 133,
"Accounting for Derivative Instruments and Hedging Activities" (SFAS 133). SFAS
133, as amended, establishes accounting and reporting standards for derivative
instruments, including certain derivative instruments embedded in other
contracts, and for hedging activities. We are required to adopt SFAS 133
effective January 1, 2001.

                                      F-11
<PAGE>
                          TITAN PHARMACEUTICALS, INC.
                         (A DEVELOPMENT STAGE COMPANY)

             NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

1.  ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (CONTINUED)
Because we currently do not hold any derivative instruments and do not engage in
hedging activities, we do not believe that the adoption of SFAS 133 will have an
impact on our financial position or results of operations.

    In December 1999, the Securities and Exchange Commission issued Staff
Accounting Bulletin No. 101, "Revenue Recognition in Financial Statements" (SAB
101), which, among other things, describes the SEC Staff's position on the
recognition of certain non-refundable up-front fees received in connection with
research collaborations. We are currently evaluating the applicability of SAB
101 to our existing collaboration agreements. Should we conclude that the
approach described in SAB 101 is more appropriate, we will change our method of
accounting effective January 1, 2000 to recognize such fees over the term of the
related research agreement.

2.  FURNITURE AND EQUIPMENT

    Furniture and equipment consisted of the following at December 31:

<TABLE>
<CAPTION>
                                                          1999        1998
                                                        ---------   ---------
<S>                                                     <C>         <C>
Furniture and office equipment........................  $ 199,049   $ 233,433
Laboratory equipment..................................    323,754     250,459
Computer equipment....................................    110,805     206,344
                                                        ---------   ---------
                                                          633,608     690,236
Less accumulated depreciation.........................   (218,785)   (273,280)
                                                        ---------   ---------
Furniture and equipment, net..........................  $ 414,823   $ 416,956
                                                        =========   =========
</TABLE>

    Depreciation expense was $173,726, $121,850 and $213,743 for the years ended
December 31, 1999, 1998 and 1997, respectively.

3.  SPONSORED RESEARCH AND LICENSE AGREEMENTS

    We have entered into various agreements with research institutions,
universities, and other entities for the performance of research and development
activities and for the acquisition of licenses related to those activities.
Expenses under these agreements totaled $1,285,265, $1,561,981 and $2,104,105 in
the years ended December 31, 1999, 1998 and 1997, respectively.

    At December 31, 1999, the annual aggregate commitments we have under these
agreements, including minimum license payments, are as follows:

<TABLE>
<S>                                                           <C>
2000........................................................  $1,486,836
2001........................................................     518,000
2002........................................................     428,000
2003........................................................     428,000
2004........................................................     428,000
                                                              ----------
                                                              $3,288,836
                                                              ==========
</TABLE>

                                      F-12
<PAGE>
                          TITAN PHARMACEUTICALS, INC.
                         (A DEVELOPMENT STAGE COMPANY)

             NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

3.  SPONSORED RESEARCH AND LICENSE AGREEMENTS (CONTINUED)
    After 2004, we must make annual payments aggregating $428,000 per year to
maintain certain licenses. Certain licenses provide for the payment of royalties
by us on future product sales, if any. In addition, in order to maintain these
licenses and other rights during product development, we must comply with
various conditions including the payment of patent related costs and obtaining
additional equity investments.

4.  LEASES

    We lease facilities under operating leases that expire at various dates
through October 2003. Rent expense was $331,048, $328,065 and $397,133 for years
ended December 31, 1999, 1998 and 1997, respectively.

    The following is a schedule of future minimum lease payments at
December 31, 1999:

<TABLE>
<S>                                                           <C>
2000........................................................     380,815
2001........................................................     415,320
2002........................................................     256,208
2003........................................................      78,413
                                                              ----------
                                                              $1,130,756
                                                              ==========
</TABLE>

5.  BANK LINE OF CREDIT

    We have available a bank line of credit that expires in March 2000, under
which $5,000,000 is available. The agreement contains covenants that require us
to maintain certain financial ratios. At December 31, 1999, we had no
outstanding balance under this line of credit and were in compliance with the
required covenants.

6.  STOCKHOLDERS' EQUITY

    PREFERRED STOCK

    In connection with the Trilex Merger in October 1997, we issued 222,400
shares of Series C Preferred to certain members of the Trilex management team
and to certain consultants of Trilex. The Series C Preferred automatically
converts to common stock, on a one-to-one basis, only if certain development
milestones are achieved, within certain timeframes. Holders of Series C
Preferred are entitled to receive dividends, when, as and if declared by the
board of directors ratably with any declaration or payment of any dividend on
our common stock or other junior securities. The Series C Preferred has a
liquidation preference equal to $0.01 per share. No value was assigned to the
Series C Preferred in the accompanying financial statements.

    In November 1997, we issued to Novartis Pharma AG (Novartis) 606,061 shares
of Series D convertible preferred stock (the Series D Preferred), pursuant to an
agreement by which we granted certain technology rights to Novartis (see Note
11). The Series D Preferred were issued pursuant to a stock purchase agreement
which provides for conversion of such shares into our common stock at the option
of Novartis at any time after January 29, 1999. The conversion price equals the
market price during a specified period within the first two fiscal quarters of
1999 and is subject to a floor of $7.50 and a ceiling of

                                      F-13
<PAGE>
                          TITAN PHARMACEUTICALS, INC.
                         (A DEVELOPMENT STAGE COMPANY)

             NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

6.  STOCKHOLDERS' EQUITY (CONTINUED)
$9.00. Accordingly, upon conversion of the Series D Preferred, we would issue a
minimum of 555,555 and a maximum of 666,667 shares of common stock (see Note
14).

    COMMON STOCK

    In January 1996, we issued 3,200,000 units at $5.00 per unit in our initial
public offering (IPO). Each unit consisted of one share of common stock and one
redeemable Class A warrant. The net proceeds (after underwriter's discount and
expenses, and other costs associated with the IPO) totaled $13,690,357. At the
closing of the offering, all of our then outstanding Series A and Series B
preferred stock automatically converted into common stock. In February 1996, we
issued an additional 480,000 units, at $5.00 per unit, in accordance with the
underwriter's over-allotment option. The net proceeds of the underwriter's over-
allotment option totaled $2,160,000.

    In July and August 1996, we completed a private placement (the Private
Placement) of 1,536,000 units, each unit consisting of one share of common stock
and one redeemable Class A warrant, for net proceeds of $13,739,628, after
deducting placement agent fees and other expenses of the private placement.

    In January 1999, we completed a private placement of 2,254,545 shares of our
common stock for net proceeds of $5,797,159, after deducting fees and
commissions and other expenses of the offering.

    WARRANTS

    During 1996 in connection with the IPO, repayment of a bridge financing and
the Private Placement, we issued 7,091,000 Class A Warrants. They entitle the
holder to purchase one share of common stock at an adjusted exercise price of
$6.02 at any time up to January 2001. The warrants are subject to redemption at
$0.05 per warrant on 30 days written notice if the closing bid price of our
common stock averages in excess of $9.10 per share for 30 consecutive trading
days ending within 15 days of the date of notice of redemption.

    In October 1999, upon satisfying the conditions for warrant redemption, we
called for the redemption on November 19, 1999 (the Redemption Date) of our
outstanding Class A Warrants for cash at the redemption price of $0.05 per
warrant. Rather than surrendering the warrants for redemption, warrant holders
had the option to purchase our common stock at a price of $6.02 per share before
the Redemption Date. The warrant call resulted in 7,083,711 of our then
outstanding Class A Warrants being exercised with net proceeds to us totaled
$39,391,635, after deducting advisory fee and other related expenses.

    UNIT PURCHASE OPTIONS

    In connection with our IPO, the underwriter was granted an option (Unit
Purchase Option) to acquire 320,000 additional units at a price of $6.50 per
unit, and in connection with the Private Placement, the placement agent was
granted a Unit Purchase Option to purchase an additional 321,065 units, as
adjusted, at an adjusted exercise price of $9.97 per unit. Each unit consists of
one share of common stock and one Class A warrant. In 1999, 247,573 units were
exercised, primarily on a cashless basis, resulting in the issuance of 124,449
shares of our common stock.

                                      F-14
<PAGE>
                          TITAN PHARMACEUTICALS, INC.
                         (A DEVELOPMENT STAGE COMPANY)

             NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

6.  STOCKHOLDERS' EQUITY (CONTINUED)

    SHARES RESERVED FOR FUTURE ISSUANCE

    As of December 31, 1999, shares of common stock reserved by us for future
issuance consisted of the following:

<TABLE>
<S>                                                           <C>
Warrants related to certain private financing transactions
  in 1995...................................................     164,856
Unit purchase options (including underlying Class A
  warrants).................................................     790,930
Stock options...............................................   3,680,618
Preferred stock.............................................     889,067
                                                              ----------
                                                               5,525,471
                                                              ==========
</TABLE>

7.  STOCK OPTION PLANS

    Under our 1993 Option Plan, as amended and restated, 558,073 shares of
common stock were reserved and authorized for issuance upon exercise of stock
options. In November 1995, we adopted the 1995 Stock Option Plan under which
1,300,000 shares of our common stock were reserved and authorized for issuance.
In June 1998, we adopted the 1998 Stock Option Plan under which 1,000,000 shares
were reserved and authorized for issuance. The option plans provide for the
grant of incentive stock options to employees, and non-qualified stock options
to employees, directors and consultants. Options granted under the option plans
generally expire no later than ten years from the date of grant, except when the
grantee is a 10% shareholder, in which case the maximum term is five years from
the date of grant. Options generally vest at the rate of one fourth after one
year from the date of grant and the remainder ratably over the subsequent three
years, although options with different vesting terms are granted from
time-to-time. The exercise price of incentive stock options, non-qualified stock
options and options granted to 10% stockholders, shall be at least 100%, 85% and
110%, respectively, of the fair market value of the stock on the date of grant.

    Options granted under the 1993 Option Plan are exercisable immediately upon
grant, however, the shares issuable upon exercise of the options are subject to
repurchase by us. Such repurchase rights will lapse over a period of up to five
years from the date of grant. At December 31, 1999, 24,064 shares of common
stock underlying the options would be subject to repurchase. No further options
will be granted under the 1993 Option Plan.

    The 1995 and 1998 Option Plans provide for the automatic grant of
non-qualified stock options to our directors who are not 10% stockholders
(Eligible Directors). Each Eligible Director will be granted an option to
purchase 10,000 shares of common stock on the date that such person is first
elected or appointed a director. In addition, each Eligible Director generally
receives an annual automatic grant of an option to purchase 5,000 shares of
common stock on the day immediately following the date of each annual
stockholders meeting, as long as such director is a member of the Board of
Directors.

    In November 1999 and in connection with the warrant call, we granted 813,000
non-qualified stock options outside of our stock option plans to our executive
officers, at an exercise price of $12.75, vesting equally over 36 months from
the date of grant.

                                      F-15
<PAGE>
                          TITAN PHARMACEUTICALS, INC.
                         (A DEVELOPMENT STAGE COMPANY)

             NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

7.  STOCK OPTION PLANS (CONTINUED)
    Activity under the 1993, 1995, and 1998 Option Plans, as well as non-plan
activity are summarized below:

<TABLE>
<CAPTION>
                                                          NUMBER OF
                                      SHARES AVAILABLE     OPTIONS     WEIGHTED AVERAGE
                                         FOR GRANT       OUTSTANDING    EXERCISE PRICE
                                      ----------------   -----------   ----------------
<S>                                   <C>                <C>           <C>
Balance at December 31, 1996........        219,365       1,402,306         $ 7.90
  Increase in shares reserved.......        452,475              --             --
  Options granted...................       (588,100)        588,100         $ 3.46
  Options exercised.................             --          (5,117)        $ 0.59
  Options cancelled.................         39,563        (168,256)        $ 3.99
                                         ----------       ---------
Balance at December 31, 1997........        123,303       1,817,033         $ 6.88
  Increase in shares reserved.......      1,000,000              --             --
  Options granted...................     (1,102,135)      1,102,135         $ 6.82
  Options exercised.................             --         (70,994)        $ 3.00
  Options cancelled.................        846,697        (923,919)        $10.10
                                         ----------       ---------
Balance at December 31, 1998........        867,865       1,924,255         $ 5.45
  Increase in shares reserved.......        225,888              --             --
  Options granted...................       (783,788)      1,596,788         $ 8.12
  Options exercised.................             --        (147,225)        $ 3.32
  Options cancelled.................         66,647         (69,812)        $ 4.84
                                         ----------       ---------
Balance at December 31, 1999........        376,612       3,304,006         $ 6.82
                                         ==========       =========
</TABLE>

    The 1995 and 1998 Option Plans allow for stock options issued as the result
of a merger or consolidation of another entity, including the acquisition of
minority interest of our subsidiaries, to be added to the maximum number of
shares provided for in the plan (Substitute Options). Consequently, Substitute
Options are not returned to the shares reserved under the plan when cancelled.
During 1999, 1998 and 1997, 3,165, 72,296 and 123,576 Substitute Options,
respectively, were cancelled and are included as shares expired during the year.

    In June 1998, we adopted an Option Exchange Program whereby certain employee
stock options which were previously granted at exercise prices greater than
$10.75 per share were exchanged for new options with an exercise price of $7.50
per share. Notwithstanding the original vesting schedule, all exchanged options
vested as of the exchange date are considered vested under the new options and
the unvested portion will vest ratably over 24 months and have a term of
approximately eight years. A total of 820,135 options with a weighted-average
exercise price of $10.91 were exchanged and reflected as grants and
cancellations in the above summary table.

                                      F-16
<PAGE>
                          TITAN PHARMACEUTICALS, INC.
                         (A DEVELOPMENT STAGE COMPANY)

             NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

7.  STOCK OPTION PLANS (CONTINUED)
    Options for 1,167,265 and 713,545 shares were exercisable at December 31,
1998 and 1997, respectively. The options outstanding at December 31, 1999 have
been segregated into three ranges for additional disclosure as follows:

<TABLE>
<CAPTION>
                                           OPTIONS OUTSTANDING
                            -------------------------------------------------        OPTIONS EXERCISABLE
                                          WEIGHTED AVERAGE                      ------------------------------
                              NUMBER         REMAINING       WEIGHTED AVERAGE     NUMBER      WEIGHTED AVERAGE
RANGE OF EXERCISE PRICES    OUTSTANDING   CONTRACTUAL LIFE    EXERCISE PRICE    EXERCISABLE    EXERCISE PRICE
------------------------    -----------   ----------------   ----------------   -----------   ----------------
<S>                         <C>           <C>                <C>                <C>           <C>
$0.080 - $4.140...........   1,093,483          7.41              $ 2.34           934,266         $ 2.25
$4.344 - $7.500...........   1,291,423          8.10              $ 6.89         1,090,800         $ 6.95
$8.500 - $12.750..........     877,100          9.85              $12.49            32,582         $11.64
                             ---------                                           ---------
$0.080 - $12.750..........   3,262,006          8.33              $ 6.87         2,057,648         $ 4.89
                             =========                                           =========
</TABLE>

    In addition, Ingenex has a stock option plan under which options to purchase
common stock of Ingenex have been and may be granted.

8.  FAIR VALUE OF STOCK OPTIONS

    We have elected to follow APB 25 in accounting for our stock options because
the alternative fair value method of accounting prescribed by SFAS 123 requires
the use of option valuation models that were not developed for use in valuing
employee stock options. Under APB 25, no compensation expense is recognized when
the exercise price of our stock options equals the market price of the
underlying stock on the date of grant.

    Pro forma net loss and net loss per share information required by SFAS 123
has been determined as if we had accounted for our employee stock options
granted subsequent to 1994 under the fair value method of SFAS 123. The fair
value for these options was estimated at the date of grant using a Black-Scholes
option pricing model with the following assumptions for 1999, 1998 and 1997:
weighted-average volatility factor of 0.8, 0.7, and 0.7, respectively; no
expected dividend payments; weighted-average risk-free interest rates in effect
of 6.0%, 5.5%, and 5.5%, respectively; and a weighted-average expected life of
2.52, 2.86, and 3.79, respectively.

    The Black-Scholes option valuation model was developed for use in estimating
the fair value of traded options which have no vesting restrictions and are
fully transferable. In addition, option valuation models require the input of
highly subjective assumptions including the expected stock price volatility.
Because our employee stock options have characteristics significantly different
from those of traded options, and because changes in the subjective input
assumptions can materially affect the fair value estimate, in management's
opinion, the existing models do not necessarily provide a reliable single
measure of the fair value of our employee stock options.

    Based upon the above methodology, the weighted-average fair value of options
granted during the years ended December 31, 1999, 1998 and 1997 was $4.83,
$1.87, and $1.90, respectively.

                                      F-17
<PAGE>
                          TITAN PHARMACEUTICALS, INC.
                         (A DEVELOPMENT STAGE COMPANY)

             NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

8.  FAIR VALUE OF STOCK OPTIONS (CONTINUED)
    For purposes of SFAS 123 disclosures, the estimated fair value of the
options is amortized to expense over the options' vesting period. Our pro forma
information is as follows:

<TABLE>
<CAPTION>
                                                                     DECEMBER 31,
                                                       -----------------------------------------
                                                           1999           1998          1997
                                                       ------------   ------------   -----------
<S>                                                    <C>            <C>            <C>
Pro forma net loss attributable to common
  stockholders.......................................  $(13,487,062)  $(11,354,801)  $(2,065,259)
Pro forma net loss per share.........................  $      (0.84)  $      (0.87)  $     (0.16)
</TABLE>

The consolidated pro forma net loss calculated above includes the estimated fair
value of the options granted by our subsidiaries in 1999, 1998 and 1997,
calculated on substantially equivalent assumptions.

9.  EQUITY IN LOSS OF ANSAN PHARMACEUTICALS, INC.

    Ansan Pharmaceuticals, Inc. was a majority owned consolidated subsidiary
until its public offering in August 1995, at which time it became an equity
method investee of Titan.

    In November 1997, the stockholders of Ansan approved an Agreement and Plan
of Reorganization and Merger between Ansan and Discovery Laboratories, Inc.,
pursuant to which Discovery was merged with and into Ansan. Pursuant to the
merger, we acquired an exclusive worldwide license to Ansan's butyrate compounds
for anti-cancer and certain other indications in exchange for our payment of a
2% royalty on net sales and transfer to Ansan of all of our equity holdings in
Ansan. Upon completion of the merger, Ansan repaid approximately $1,170,000 of
outstanding indebtedness to us.

    Our share of Ansan is net loss of $590,853 for the period ended
December 31, 1997 represents the entire carrying value of the investment at
December 31, 1996 as the allocable portion of Ansan's loss exceeded the book
value of the investment.

10.  AGREEMENT WITH HOECHST MARION ROUSSEL

    In January 1997, we entered into an exclusive license agreement with Hoechst
Marion Roussel, Inc. (Hoechst). The agreement gave us a worldwide license to
Hoechst's patent rights and know-how related to the antipsychotic agent
iloperidone, including the ability to develop, use, sublicense, manufacture and
sell products and processes claimed in the patent rights. Pursuant to the
license, we paid, during 1997, a fee of $9,500,000, consisting of: (i)
$4,000,000 in cash, and (ii) $5,500,000 through the issuance of 594,595 shares
of common stock (the Hoechst Shares.) We were obligated to pay to Hoechst the
difference between $5,500,000 and the net proceeds received by Hoechst upon sale
of the Hoechst Shares. In February 1998, Hoechst sold the Hoechst Shares for net
proceeds of $2,455,591. Accordingly, we paid to Hoechst $3,044,409 in cash and
the remaining balance of $2,455,591 was transferred to stockholders' equity. We
are required to make additional benchmark payments as specific milestones are
met. Upon commercialization of the product, the license agreement provides that
we will pay royalties based on net sales.

11.  ZOMARIL-TM- (ILOPERIDONE) SUBLICENSE

    In November 1997, we entered into an agreement with Novartis, pursuant to
which we granted Novartis a sublicense for the worldwide (with the exception of
Japan) development, manufacturing and marketing of Zomaril-TM- (iloperidone).
Pursuant to the sublicense, Novartis paid to us $20,000,000 consisting of a fee
of $15,000,000 and $5,000,000 for the purchase of 606,061 shares of Series D
convertible

                                      F-18
<PAGE>
                          TITAN PHARMACEUTICALS, INC.
                         (A DEVELOPMENT STAGE COMPANY)

             NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

11.  ZOMARIL-TM- (ILOPERIDONE) SUBLICENSE (CONTINUED)
preferred stock. In addition, approximately $2,400,000 in cash was paid by
Novartis as reimbursement of research and development costs incurred by us. The
Novartis sublicense provides for future payments by Novartis contingent upon the
achievement of regulatory milestones as well as a royalty on net sales, if any,
of the product. Novartis has assumed the responsibility for all clinical
development, registration and marketing of Zomaril-TM-.

12.  MINORITY INTEREST

    The $1,241,032 received by Ingenex upon the issuance of its Series B
convertible preferred stock has been classified as minority interest in the
consolidated balance sheet. As a result of the Series B preferred stockholders'
liquidation preference, the balance has not been reduced by any portion of the
losses of Ingenex.

    Amounts invested by outside investors in the common stock of the
consolidated subsidiaries have been apportioned between minority interest and
additional paid-in capital in the consolidated balance sheets. Losses applicable
to the minority interest holdings of the subsidiaries' common stock have been
reduced to zero.

13.  INCOME TAXES

    As of December 31, 1999, we had federal and state net operating loss
carryforwards of approximately $58,200,000 and $21,600,000, respectively. We
also had federal research and development tax credit carryforwards of
approximately $1,400,000. The net operating loss and credit carryforwards will
expire at various dates beginning in 2000 through 2019, if not utilized.

    Under provisions of the Internal Revenue Code, the availability of our net
operating loss and tax credit carryforwards may be subject to future limitations
because of changes in ownership resulting from financing transactions. To date,
no such restriction in the availability to utilize our carryforwards is
anticipated. However, future equity transactions which we may enter into could
cause ownership changes which may result in substantial limitation, or
expiration, of loss and tax credit carryforwards.

    Deferred tax assets and liabilities reflect the net tax effects of net
operating losses and temporary differences between the carrying amount of assets
and liabilities for financial reporting and amounts used

                                      F-19
<PAGE>
                          TITAN PHARMACEUTICALS, INC.
                         (A DEVELOPMENT STAGE COMPANY)

             NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (CONTINUED)

13.  INCOME TAXES (CONTINUED)
for income tax purposes. Significant components of our deferred tax assets for
federal and state income taxes are as follows:

<TABLE>
<CAPTION>
                                                          DECEMBER 31,
                                                   ---------------------------
                                                       1999           1998
                                                   ------------   ------------
<S>                                                <C>            <C>
Deferred tax assets:
  Net operating loss carryforwards...............  $ 21,000,000   $ 14,500,000
  Research credit carryforwards..................     1,400,000      1,400,000
  Capitalized research and development...........     2,300,000      1,500,000
  Other - net....................................       800,000      1,400,000
                                                   ------------   ------------
Total deferred tax assets........................    25,500,000     18,800,000
Valuation allowance..............................   (25,500,000)   (18,800,000)
                                                   ------------   ------------
Net deferred tax assets..........................  $         --   $         --
                                                   ============   ============
</TABLE>

    For 1998 and 1997, the valuation allowance increased by $4,300,000 and
$100,000, respectively.

14.  SUBSEQUENT EVENTS

    COLLABORATION WITH SCHERING AG

    In January 2000, we entered into an agreement with Schering AG, under which
Schering and we will collaborate on manufacturing and clinical development of
cell therapy for the treatment of Parkinson's disease. We will receive funding
for development activities, as well as potential reimbursement of certain prior
research and development expenses. Schering will fully fund, and manage in
collaboration with us, all future pilot and pivotal clinical studies, and
manufacturing and development activities. Under this agreement, Schering
received exclusive, worldwide development, manufacturing and commercialization
rights, and, in addition to the above payments, agreed to pay us a royalty on
product sales. Schering also retains the right to make an equity investment in
us, up to a specified amount, upon initiation of pivotal clinical studies. In
addition to the collaborative development of Spheramine for Parkinson's disease,
Titan and Schering will also mutually explore other potential therapeutic
applications of our CCM technology, under a one year exclusive option granted to
Schering by us.

    PRIVATE PLACEMENT

    In March 2000, we completed a private placement of 1,200,000 shares of our
common stock for net proceeds of approximately $38,900,000, after deducting fees
and commissions and other expenses of the offering.

    CONVERSION OF SERIES D PREFERRED

    In March 2000, upon satisfying the conditions for conversion and at the
request of Novartis, all outstanding Series D Preferred shares were converted
into 666,667 shares of our common stock.

                                      F-20
<PAGE>
                                   SIGNATURES

    Pursuant to the requirements of Section 13 of the Securities and Exchange
Act of 1934, the Registrant has duly caused this report to be signed on its
behalf by the undersigned, thereunto duly authorized.

<TABLE>
<S>                                                    <C>  <C>
                                                       TITAN PHARMACEUTICALS, INC.

                                                       By:             /s/ LOUIS R. BUCALO
                                                            -----------------------------------------
Date: March 30, 2000                                                  Louis R. Bucalo, M.D.,
                                                             CHAIRMAN, PRESIDENT AND CHIEF EXECUTIVE
                                                                             OFFICER
</TABLE>

    Pursuant to the requirements of the Securities Exchange Act of 1934, this
report has been signed below by the following persons in the capacities and on
the dates stated.

<TABLE>
<CAPTION>
                      SIGNATURE                                   TITLE                    DATE
                      ---------                                   -----                    ----
<C>                                                    <S>                          <C>
                                                       Chairman, President and
                 /s/ LOUIS R. BUCALO                     Chief Executive Officer
     -------------------------------------------         (principal executive         March 30, 2000
                Louis R. Bucalo, M.D.                    officer)

               /s/ ERNST-GUNTER AFTING
     -------------------------------------------       Director                       March 30, 2000
          Ernst-Gunter Afting, M.D., Ph.D.

                 /s/ VICTOR J. BAUER
     -------------------------------------------       Director                       March 30, 2000
               Victor J. Bauer, Ph.D.

               /s/ EURELIO M. CAVALIER
     -------------------------------------------       Director                       March 30, 2000
                 Eurelio M. Cavalier

                 /s/ MICHAEL K. HSU
     -------------------------------------------       Director                       March 30, 2000
                   Michael K. Hsu

                /s/ HUBERT E. HUCKEL
     -------------------------------------------       Director                       March 30, 2000
               Hubert E. Huckel, M.D.

                 /s/ MARVIN E. JAFFE
     -------------------------------------------       Director                       March 30, 2000
                Marvin E. Jaffe, M.D.

                 /s/ KONRAD M. WEIS
     -------------------------------------------       Director                       March 30, 2000
                Konrad M. Weis, Ph.D.

                                                       Executive Vice President
                /s/ ROBERT E. FARRELL                    and Chief Financial
     -------------------------------------------         Officer (principal           March 30, 2000
                  Robert E. Farrell                      financial and accounting
                                                         officer)
</TABLE>