<PAGE>   1
                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM 10-K

(Mark One)

[X] ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT
OF 1934

For the fiscal year ended June 30, 1998 or

[ ] TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE
ACT OF 1934

For the transition period from __________ to __________

                          Commission file number 1-9860

                            BARR LABORATORIES, INC.
             (Exact name of Registrant as specified in its charter)

           NEW YORK                                               22-1927534
(State or Other Jurisdiction of                              (I.R.S. - Employer
 Incorporation or Organization)                              Identification No.)

          TWO QUAKER ROAD, P. O. BOX 2900, POMONA, NEW YORK 10970-0519
                    (Address of principal executive offices)

                                  914-362-1100
                         (Registrant's telephone number)

      Securities registered pursuant     Name of each exchange on
       to Section 12(b) of the Act:         which registered:
            Title of each class
       Common Stock, Par Value $0.01     New York Stock Exchange

             Securities registered pursuant to Section 12(g) of the
                           Act: None (Title of Class)

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 12 months (or for such shorter period that the registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 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 of the Registrant held by
nonaffiliates was approximately $527,693,496 as of June 30, 1998 (assuming
solely for purposes of this calculation that all Directors and Officers of the
Registrant are "affiliates").

Number of shares of Common Stock, Par Value $.01, outstanding as of June 30,
1998: 22,306,690.

                       DOCUMENTS INCORPORATED BY REFERENCE

PORTIONS OF THE REGISTRANT'S 1998 ANNUAL REPORT TO SHAREHOLDERS ARE INCORPORATED
BY REFERENCE IN PART II AND PART IV HEREOF. PORTIONS OF THE REGISTRANT'S 1998
PROXY STATEMENT ARE INCORPORATED BY REFERENCE IN PART III HEREOF.

<PAGE>   2

                                     PART I

ITEM 1. BUSINESS

Barr Laboratories, Inc. ("Barr" or the "Company") is an established
pharmaceutical company engaged in the development, manufacture and marketing of
generic and proprietary prescription pharmaceuticals. The Company was founded in
1970 by Mr. Edwin A. Cohen and a partner, and commenced active business in 1972
as a manufacturer of generic drug products. Barr is listed on the New York Stock
Exchange (NYSE-BRL).

The Company currently markets 70 products, representing various dosage strengths
and product forms of 34 chemical entities. The Company's product line is
concentrated primarily on six core therapeutic categories: oncology, female
healthcare, cardiovascular, anti-infectives, pain management and
psychotherapeutics.

The Company's business strategy has three core components: (i) the development
and marketing of generic pharmaceuticals that have one or more barriers to
entry, (ii) challenging patents protecting select brand pharmaceuticals where
the Company believes that such patents are either invalid, unenforceable or not
infringed by the Company's product, and (iii) the development and introduction
of proprietary pharmaceuticals most of which will have some form of market
exclusivity.

Generic pharmaceuticals represent an increasing proportion of medicines
dispensed in the U.S. In 1996, the U.S. generic pharmaceutical industry had
total U.S. sales of approximately $9 billion. Industry sources also estimate
that pharmaceuticals with 1996 U.S. sales in excess of $6 billion are already
off-patent and have no generic competition. In addition, industry sources
estimate that, through the year ended 2002, branded drugs with 1996 U.S. sales
of approximately $11 billion will lose patent protection. The Company believes
that the market for generic pharmaceuticals will continue to grow, driven by two
primary factors. The first factor is the future commercialization of generic
versions of drugs with patents that (i) have already expired or (ii) will expire
over the next several years. The Company believes a second factor driving growth
will be increasing rates at which generic pharmaceuticals are substituted for
branded drugs.

The marketplace economics that impact the much larger, multi-national
pharmaceutical companies may limit their willingness to provide orphan drug
products or therapies where the patient population is too small to provide a
sufficient return on investment. The Company believes that these areas could
provide an opportunity for limited competition for proprietary products.

Current Products and Supply Agreements

The Company's largest selling product is Tamoxifen Citrate ("Tamoxifen"), the
generic equivalent of Nolvadex(R), which is used to treat advanced breast cancer
as well as impede the recurrence of tumors following surgery. Tamoxifen
accounted for approximately 68%, 76% and 74% of the Company's net product sales
during fiscal 1998, 1997 and 1996, respectively.

In 1993, as a result of a settlement of a patent challenge against the Innovator
of Tamoxifen, the Company entered into a non-exclusive supply and distribution
agreement (the "Tamoxifen Agreement"). Under the terms of the Tamoxifen
Agreement, Barr purchases Tamoxifen directly from the Innovator and sells it as
a generic product. The Company is the only distributor of


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Tamoxifen in the U.S. other than the Innovator. Although it is a non-exclusive
distributor, the Tamoxifen Agreement provides that should an additional
distributor or distributors be selected by the Innovator, Barr will be granted
terms no less favorable than those granted to any subsequent distributor.
Furthermore, the Company has a tentatively approved Abbreviated New Drug
Application ("ANDA") for the manufacture of Tamoxifen. Therefore, at the time of
patent expiration in August 2002 (or should another company's patent challenge
succeed), Barr will be permitted to immediately begin the direct manufacture of
Tamoxifen. Manufacturing Tamoxifen would significantly lower Barr's cost of
goods for this product and the Company believes its profit margins on Tamoxifen
would improve. Within the last 24 months, a court upheld the Tamoxifen patent in
a challenge brought by another generic pharmaceutical company. In addition, the
Company is aware of 2 other challenges currently pending against Tamoxifen.
Although the final outcome of any such litigation is uncertain, to date no other
challenge to Tamoxifen has been successful.

The Company's most significant recent product introduction is Warfarin Sodium,
which was launched by the Company in July 1997. Warfarin Sodium is the generic
equivalent of DuPont Pharmaceutical Company's Coumadin(R), an anti-coagulant
that is given to patients with heart disease and/or high risk of stroke.
Coumadin had U.S. sales of approximately $535 million in 1997. Although another
generic competitor has received an ANDA approval for Warfarin Sodium, Barr is
currently the only company marketing a generic equivalent of Coumadin. The
Company believes that there will be limited generic competition for this product
because of a number of barriers to entry, including difficulty of sourcing raw
material, the need for specialized manufacturing facilities and marketing
barriers created by DuPont Pharmaceutical Company to oppose generic
substitution.

In January 1997, the Company and the Innovator of Ciprofloxacin settled pending
patent litigation. Ciprofloxacin is the generic equivalent of Bayer's Cipro(R),
which is used to treat lower respiratory, skin, bone and joint, and urinary
tract infections. As part of the settlement of the patent challenge, the Company
entered into a contingent, non-exclusive supply agreement (the "Ciprofloxacin
Agreement") which ends with the expiration of the patent in December 2003. Under
the Ciprofloxacin Agreement, the Innovator has the option to make payments to
Barr or to provide Barr with quantities of Ciprofloxacin that Barr would market
as a generic pursuant to a license from the Innovator. If the Innovator chooses
not to provide the product to Barr, Barr would receive quarterly income and cash
flow of $6 million to $8 million throughout the life of the Ciprofloxacin
Agreement. In August, the Company was notified that another challenge was filed
against Ciprofloxacin. Although the timing and final outcome of any such
litigation is uncertain, the Company believes that it will be several years
before any litigation regarding Ciprofloxacin is finally adjudicated.

Product Development

The Company's objective is to utilize its research and development and
manufacturing capabilities to maximize return on shareholder investment. To
achieve this objective, the Company focuses it resources on three core
strategies:

Development and Marketing of Selected Generic (Off-Patent) Pharmaceuticals. The
Company principally pursues the development and marketing of generic
pharmaceuticals that have one or more barriers to entry. The Company rarely
pursues those products where it expects that a significant number of its
competitors will successfully develop a generic product. The Company


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believes products with such barriers will face limited competition and therefore
provide longer product life-cycles and/or higher profitability than commodity
generic products.

Challenging Patents Protecting Certain Brand Pharmaceuticals. The Company
pursues development and marketing of branded pharmaceuticals protected by
patents where the Company believes that such patents are either invalid or not
infringed by the Company's product. This strategy is an extension of the
Company's generic strategy, in that, issued patents, even invalid patents,
present barriers to entry to companies that do not have the capabilities to
assess and challenge the validity of such patents. The Company believes that the
successful development of pharmaceuticals that were perceived by competitors to
be patent protected may offer longer product life-cycles and/or higher
profitability.

Development and Introduction of Proprietary Pharmaceuticals. The Company is
pursuing the development of proprietary pharmaceuticals that may have some
period of exclusivity, typically from three to seven years. The Company believes
that such products will produce higher and more consistent profitability than
the typical generic product. The Company anticipates that the majority of its
proprietary products will be developed with strategic partners and marketed by
those partners through detail product sales forces or other appropriate
channels.

In September, the FDA approved the first product from Barr's proprietary product
development program - a contraceptive co-developed with Gynetics, Inc. The
product, the PREVEN(TM) Emergency Contraceptive Kit, is the first FDA-approved
product specifically designed to prevent pregnancy within 72 hours of
unprotected intercourse. Barr helped to develop and submit the new product
application to the FDA and will manufacture the oral contraceptive tablets that
are part of the PREVEN Kit. Gynetics will be responsible for marketing the
product.

For the fiscal years ended June 30, 1998, 1997, and 1996, total research and
development expenditures were approximately $19 million, $14 million and $11
million, respectively. Management anticipates that research and development
expenditures in fiscal 1999 will exceed comparable expenditures in fiscal 1998.

Marketing and Customers

The Company markets its products to customers in the United States and Puerto
Rico through an integrated sales and marketing force. The activities of the
sales force are supplemented by customer service representatives who inform the
Company's customers of new products, process orders and advise of order status
and current pricing.

The Company's customer base includes drug store chains, food chains, mass
merchandisers, wholesalers, distributors, managed care organizations, mail order
accounts, government/military and repackagers. The Company's products are sold
under the Barr label as well as private labels of several distributors.

The Company has approximately 180 direct purchasing customers and 100 indirect
customers that purchase the Company's products via wholesalers. In fiscal 1998,
1997 and 1996, McKesson Drug Company, the nations largest wholesaler, accounted
for approximately 12%, 13% and 10%, respectively, of net product sales. No other
customer accounted for greater than 10% of sales in any of the last three fiscal
years.


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During the past two years the Company's customer base underwent significant
consolidation, particularly in the chain drug store, distributor and wholesaler
trade classes. To date, this consolidation has had no adverse impact on the
Company's business. The Company believes that it has excellent relationships
with its key customers, but there can be no assurance that continued
consolidation will not impact the Company's business, or that such impact might
not be significant.

Competition

The Company competes in varying degrees with numerous other manufacturers of
pharmaceutical products (both branded and generic). These competitors include
the generic divisions of proprietary pharmaceutical companies (either marketing
units or other generic manufacturers), large independent generic
manufacturers/distributors that seek to provide "one stop shopping" by offering
a full line of products, and generic manufacturers that have targeted select
therapeutic categories and market niches.

The principal competitive factors in the generic pharmaceutical industry are:

         -        the ability to introduce generic versions of branded products
                  promptly after the expiration of market exclusivity;

         -        maintenance of sufficient inventories to ensure timely
                  deliveries;

         -        price;

         -        quality; and

         -        customer service.

Many of the Company's competitors have greater financial and other resources,
and are therefore able to devote more resources than the Company in such areas
as marketing and product development. In order to ensure its ability to compete
effectively, the Company has:

         -        focused its product development in areas of historical
                  strength or competitive advantage;

         -        targeted products for development that offer significant
                  barriers to entry for competitors, including: difficulty in
                  sourcing raw materials; difficulty in formulation or
                  establishing bioequivalence; manufacturing that requires
                  unique facilities, processes or expertise; and

         -        invested in plant and equipment to give it a competitive edge
                  in manufacturing.

These factors, when combined with the Company's investment in new product
development and its focus on select therapeutic categories, provide the basis
for its belief that it will continue to remain a leading independent generic
pharmaceutical company.

Raw Materials

The active chemical raw materials essential to the Company's business are bulk
pharmaceutical chemicals, which are purchased from numerous manufacturers in the
U.S. and throughout the world. All purchases are made in United States dollars,
and therefore, while currency fluctuations do not have an immediate impact on
prices the Company pays, such fluctuations may, over time, have an effect on
prices to the Company. In addition, because prior U.S. Food


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and Drug Administration ("FDA") approval of raw material suppliers is required,
if raw materials from an approved supplier were to become unavailable, the
required FDA approval of a new supplier could cause a significant delay in the
manufacture of the drug product affected. However, in some cases, the Company
has a FDA approved alternate supplier which would mitigate the effect of any
such delay. To date, the Company has not experienced any significant delays from
lack of raw material availability. However, there can be no assurance that
significant delays will not occur in the future.

Employees

As of June 30, 1998, the Company had approximately 557 full-time employees. Of
these, approximately one-quarter are represented by a union that has a
collective bargaining agreement with the Company. The Company's current
collective bargaining agreement with its employees, who are represented by Local
8-149 of the Oil, Chemical and Atomic Workers International Union ("OCAW"),
expires on April 1, 2001.

GOVERNMENT REGULATION

All pharmaceutical manufacturers, including the Company, are subject to
extensive regulation by the federal government, principally by the FDA, and, to
a lesser extent, by the U.S. Drug Enforcement Administration ("DEA") and state
governments. The Federal Food, Drug and Cosmetic Act, the Controlled Substances
Act and other federal statutes and regulations govern or influence the testing,
manufacturing, safety, labeling, storage, record keeping, approval, pricing,
advertising and promotion of the Company's products. Non-compliance with
applicable requirements can result in fines, recalls and seizure of products.
Under certain circumstances, the FDA also has the authority to revoke drug
approvals previously granted.

ANDA Process

FDA approval is required before a generic equivalent to a previously approved
drug or a new dosage form of an existing drug can be marketed. The Company
usually receives approval for such products by submitting an ANDA to the FDA.
When processing an ANDA, the FDA waives the requirement of conducting complete
clinical studies, although it may require bioavailability and/or bioequivalence
studies. "Bioavailability" indicates the rate and extent of absorption and
levels of concentration of a drug product in the blood stream needed to produce
a therapeutic effect. "Bioequivalence" compares the bioavailability of one drug
product with another, and when established, indicates that the rate of
absorption and levels of concentration of a generic drug in the body are
substantially equivalent to the previously approved drug. An ANDA may be
submitted for a drug on the basis that it is the equivalent to a previously
approved drug or, in the case of a new dosage form, is suitable for use for the
indications specified.

Among the requirements for drug approval by the FDA is that the Company's
manufacturing procedures and operations conform to current Good Manufacturing
Practices ("cGMP"), as defined in the U.S. Code of Federal Regulations. The cGMP
regulations must be followed at all times during the manufacture of
pharmaceutical products. In complying with the standards set forth in the cGMP
regulations, the Company must continue to expend time, money and effort in the
areas of production and quality control to ensure full technical compliance.

If the FDA believes a company is not in compliance with cGMP, certain sanctions
are imposed upon that company including (i) withholding from the company new
drug approvals as well as


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approvals for supplemental changes to existing applications; (ii) preventing the
company from receiving the necessary export licenses to export its products; and
(iii) classifying the company as an "unacceptable supplier" and thereby
disqualifying the company from selling products to federal agencies. The Company
believes it is currently in compliance with cGMP.

In May of 1992, the Generic Drug Act of 1992 (the "Act") was enacted. The Act, a
result of the legislative hearings and investigations into the generic drug
approval process, allows the FDA to impose debarment and other penalties on
individuals and companies that commit certain illegal acts relating to the
generic drug approval process. In some situations, the Act requires the FDA to
debar (i.e., not accept or review ANDAs for a period of time) a company or an
individual that has committed certain violations. It also provides for temporary
denial of approval of applications during the investigation of certain
violations that could lead to debarment and also, in more limited circumstances,
provides for the suspension of the marketing of approved drugs by the affected
company. Lastly, the Act allows for civil penalties and withdrawal of previously
approved applications. Neither the Company nor any of its employees have ever
been subject to debarment.

NDA Process

FDA approval is required before any new drug can be marketed. A New Drug
Application ("NDA") is a filing submitted to the FDA to obtain approval of a
drug not eligible for an ANDA and must contain complete pre-clinical and
clinical safety and efficacy data or a right of reference to such data. Before
dosing a new drug in healthy human subjects or patients may begin, stringent
government requirements for pre-clinical data must be satisfied. The
pre-clinical data must provide an adequate basis for evaluating both the safety
and the scientific rationale for the initiation of clinical trials.

Clinical trials are typically conducted in three sequential phases, although the
phases may overlap. Data from pre-clinical testing and clinical trials are
submitted to the FDA as a NDA for marketing approval and to other health
authorities as a marketing authorization application. The process of completing
clinical trials for a new drug may take several years and require the
expenditure of substantial resources. Preparing a NDA or marketing authorization
application involves considerable data collection, verification, analysis and
expense, and there can be no assurance that approval from the FDA or any other
health authority will be granted on a timely basis, if at all. The approval
process is affected by a number of factors, primarily the risks and benefits
demonstrated in clinical trials as well as the severity of the disease and the
availability of alternative treatments. The FDA or other health authorities may
deny a NDA or marketing authorization application if the regulatory criteria are
not satisfied, or such authorities may require additional testing or
information.

Even after initial FDA or other health authority approval has been obtained,
further studies may be required to provide additional data on safety and will be
required to gain approval for the use of a product as a treatment for clinical
indications other than those for which the product was initially tested.
Additionally, the FDA regulates post-approval promotional labeling and
advertising activities to assure that such activities are being conducted in
conformity with statutory and regulatory requirements.

DEA

Because the Company markets some and intends to introduce or reintroduce a wide
range of controlled substances in its analgesic and psychotherapeutic product
lines, it must meet the


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requirements of the Controlled Substances Act and the regulations issued
thereunder and administered by the DEA. These regulations include stringent
requirements for manufacturing controls and security to prevent diversion of or
unauthorized access to the drugs in each stage of the production and
distribution process. The DEA monitors allocation to the Company of raw
materials used in the production of controlled substances based on historical
sales data. The Company believes it is currently in compliance with all
applicable DEA requirements.

Government Relations Activities

During the past two years, the branded pharmaceutical industry has increased its
efforts to utilize state and federal legislative and regulatory forums to delay
generic competition, or limit the severe market erosion they can experience
which occurs once monopoly protection is lost for the branded product. To
achieve these goals, the brand pharmaceutical companies have attempted to use
the Citizen Petition process (i.e. petition directly to the FDA) to request
amendments to FDA standards, sought changes in United States Pharmacopeia
requirements, and sought to attach patent extension amendments to important
federal legislation. Another anti-generic defense strategy involves
state-by-state initiatives to enact legislation that would impose restrictions
on the substitution of equivalent generic drugs. Using such terminology as
narrow therapeutic index and "critical care" to define subcategories of drug
products, the brand industry is attempting to erroneously suggest that there are
clinical differences between brand and generic products that require additional
attention by the prescribing physician or limits on substitution. Since January
1997, Barr has engaged the resources necessary to fight proposed legislation in
a number of major states.

Because this issue is critical to Barr's continued success, the Company has and
will continue to put a major emphasis in terms of management time and financial
resources on government affairs activities.

Patents

The Process Patent Amendments Act of 1988 provides that the use or sale within
the United States, or importation into the United States, of a product that was
made either domestically or abroad by a process covered by a United States
patent, constitutes infringement of the process patent. After proper notice,
this legislation could subject the Company to potential patent infringement
claims if a supplier of an active ingredient to the Company were to infringe a
United States process patent in the manufacture of such ingredient. The Company
has received no such notice.

Medicaid

In November 1990, a law regarding reimbursement for prescribed Medicaid drugs
was passed as part of the Congressional Omnibus Budget Reconciliation Act of
1990. This law basically required drug manufacturers to enter into a rebate
contract with the Federal Government. All generic pharmaceutical manufacturers,
whose products are covered by the Medicaid program, are required to rebate to
each state a percentage (currently 11% in the case of products manufactured by
the Company and 15% for Tamoxifen sold by the Company) of their average net
sales price for the products in question. The Company provides an accrual for
future estimated rebates in its consolidated financial statements.


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Effect of the General Agreement on Tariffs and Trade ("GATT")

With the signing of the GATT accord in December 1994, one of the provisions
called for harmonization of patent life throughout GATT countries. U.S. enabling
legislation had provisions that in effect offered a limited extension of the
period of monopoly protection for intellectual property including patents. While
a number of patented drugs will receive extended patent protection (the maximum
extension being 36 months) as a result of this enabling legislation, the patent
extensions resulting from the implementation of GATT are not expected to
materially impact any of the product candidates in Barr's current pipeline.

Other

The Company is also governed by federal, state and local laws of general
applicability, such as laws regulating working conditions, equal employment
opportunity, and environmental protection.

ITEM 2. PROPERTIES

Barr has facilities and operations in Pomona and Blauvelt, New York; Northvale,
New Jersey; and Forest, Virginia. The following table presents the facilities
owned or leased by the Company and indicates the location and type of each of
these facilities.

<TABLE>
<CAPTION>
                     SQUARE
LOCATION             FOOTAGE       STATUS      DESCRIPTION
--------             -------       ------      -----------
<S>                  <C>           <C>         <C>
NEW JERSEY
Northvale             26,500       Owned       Manufacturing
Northvale             57,000       Leased      Warehouse

NEW YORK
Blauvelt              50,000       Leased      Corporate Administration
Pomona 1              33,000       Owned       R&D Laboratories, Manufacturing
Pomona 2              44,000       Owned       Laboratories, Administrative
                                               Offices, Manufacturing

VIRGINIA
Forest               168,000       Owned       Administrative Offices,
                                               Manufacturing, Warehouse,
                                               Packaging, Distribution
</TABLE>


Over the past three fiscal years, the Company has spent approximately $72
million in capital expenditures to expand manufacturing capacity and strengthen
certain competitive advantages.


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<PAGE>   10

ITEM 3. LEGAL PROCEEDINGS

Fluoxetine Hydrochloride Patent Challenge

In February 1996, Barr filed an ANDA seeking approval from the FDA to market
fluoxetine hydrochloride ("Fluoxetine"), the generic equivalent of Eli Lilly
Company's ("Lilly") Prozac(R). The Company notified Lilly pursuant to the
provisions of the Waxman-Hatch Act, and, on April 19, 1996, Lilly filed a patent
infringement action in the United States District Court for the Southern
District of Indiana - Indianapolis Division seeking to prevent Barr from
marketing Fluoxetine until certain U.S. patents expire in 2003. The Company is
pursuing this case vigorously and a trial date has been set for January 1999.

Invamed, Inc. Lawsuit

On February 25, 1998, Invamed, Inc. ("Invamed") named the Company and several
others as defendants in a lawsuit filed in the United States District Court for
the Southern District of New York, charging that the Company unlawfully blocked
access to the raw material source for Warfarin Sodium. The Company believes that
the suit filed against it by Invamed is without merit and intends to defend its
position vigorously. This action is currently in discovery stage. It is
anticipated that this matter will take several years to be resolved but an
adverse judgement could have a material adverse impact on the Company's
consolidated financial statements.

DuPont Anti-Trust Suit

On March 9, 1998, the Company filed an anti-trust suit against DuPont Merck
Pharmaceutical Company ("DuPont Merck") in the United States District Court for
the Southern District of New York, charging that DuPont Merck has acted
unlawfully to impede the marketplace acceptance of Barr's generic version of the
anti-coagulant Coumadin. The Company's suit charges that DuPont Merck's actions
violated federal anti-trust laws, as well as the Lanham Act and the New York
Deceptive Acts and Practices Act. The Company intends to prosecute this case
vigorously.

Miscellaneous

As of June 30, 1998, the Company was involved, as plaintiff and defendant, in
other lawsuits incidental to its business. Management of the Company, based on
the advice of legal counsel, believes that the disposition of such litigation
will not have any significant adverse effect on the Company's consolidated
financial statements.


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

None.


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                               PART II

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

The information required by Item 5 is included on page 42 of the 1998 Annual
Report to Shareholders ("Annual Report") and is incorporated herein by
reference.

ITEM 6.  SELECTED FINANCIAL DATA

The information required by Item 6 is included on page 44 of the Annual Report
and is incorporated herein by reference.

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

The information required by Item 7 is included on pages 23 through 27 of the
Annual Report and is incorporated herein by reference.

ITEM 7a.  QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

The Company's exposure to market risk for a change in interest rates relates
primarily to the Company's investment portfolio of $80 million and debt
instruments of $37 million. The Company does not use derivative financial
instruments.

The Company's investment portfolio consists of cash and cash equivalents and
marketable securities classified as "available for sale". The primary objective
of the Company's investment activities is to preserve principal while at the
same time maximizing yields without significantly increasing risk. To achieve
this objective, the Company maintains its portfolio in a variety of high credit
quality securities, including U.S. government and corporate obligations,
certificates of deposit and money market funds. Approximately 91% of the
Company's portfolio matures in less than three months and the remaining 9%
matures in less than one year. The carrying value of the investment portfolio
approximates the market value at June 30, 1998. Because the Company's
investments are diversified and are of relatively short maturity, a hypothetical
10% change in interest rates would not have a material effect on the Company's
consolidated financial statements.

Approximately 82% of the Company's debt instruments at June 30, 1998 are subject
to fixed interest rates and principal payments. The related note purchase
agreements permit the Company to prepay these notes prior to their scheduled
maturity, but would require the Company to pay a prepayment fee based on current
market rates and the note rates. The remaining 18% of debt instruments are
primarily subject to variable interest rates based on LIBOR and have fixed
principal payments. The fair value of all debt instruments is approximately $34
million at June 30, 1998. Management does not believe that any risk inherent in
the variable-rate nature of these instruments is likely to have a material
effect on the Company's consolidated financial statements.

The Company's $20 million Unsecured Revolving Credit Facility ("Revolver") has
an interest rate based on the prime rate or LIBOR plus 0.75, at the Company's
option. The Company currently maintains a zero balance on the Revolver (at June
30, 1998, the outstanding balance


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<PAGE>   12

was $2.5 million). If the Company were to draw down on the line prior to its
expiration in July 2000, and an unpredicted increase in both alternate rates
occurred, it would not be likely to have a material effect on the Company's
consolidated financial statements.

ITEM 8.  FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

The information required by Item 8 is included on pages 28 through 43 of the
Annual Report and is incorporated herein by reference.

ITEM 9.  CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING
AND FINANCIAL DISCLOSURES

None.


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                                    PART III

ITEM 10. DIRECTORS AND EXECUTIVE OFFICERS OF THE REGISTRANT

The Company's executive officers are as follows:

<TABLE>
<CAPTION>
       NAME                 AGE           POSITION
<S>                      <C>       <C>
Bruce L. Downey          50        Chairman of the Board, Chief Executive
                                   Officer and President

Paul M. Bisaro           37        Senior Vice President, Strategic Business
                                   Development, General Counsel and Secretary

Timothy P. Catlett       43        Senior Vice President, Sales and Marketing

Mary E. Petit            49        Senior Vice President, Operations

Salah U. Ahmed           44        Vice President, Product Development

Ezzeldin A. Hamza        47        Vice President, Research and Development

Catherine F. Higgins     46        Vice President, Human Resources

William T. McKee         37        Vice President, Chief Financial Officer
                                   and Treasurer

Gerald F. Price          51        Vice President, Manufacturing and
                                   Engineering
</TABLE>

         BRUCE L. DOWNEY became the Company's President, Chief Operating Officer
and a member of the Board of Directors in January 1993 and was elected Chairman
of the Board and Chief Executive Officer in February of 1994. Prior to assuming
these positions, from 1981 to 1993, Mr. Downey was a partner in the law firm of
Winston & Strawn and a predecessor firm of Bishop, Cook, Purcell and Reynolds.
Mr. Downey is also a director of Warner Chilcott plc. (NASDAQ).

         PAUL M. BISARO became the Company's General Counsel in July 1992, was
elected Secretary of the Company in September 1992 and elected a Vice President
in 1993. In August 1994, Mr. Bisaro was elected to the position of Chief
Financial Officer. In September 1996, Mr. Bisaro was elected to the position of
Senior Vice President-Strategic Business Development. In June 1998, Mr. Bisaro
was elected to the Company's Board of Directors. Prior to assuming these
positions with the Company, he was associated with the law firm of Winston &
Strawn and a predecessor firm, Bishop, Cook, Purcell and Reynolds. Prior to his
association with Winston & Strawn, Mr. Bisaro was a Consultant with Arthur
Anderson & Co.

TIMOTHY P. CATLETT was employed by the Company in February 1995 as Vice
President, Sales and Marketing. In September 1997, Mr. Catlett was elected to
Senior


                                                                              13
<PAGE>   14

Vice President of Sales and Marketing. From 1978 through 1993, Mr. Catlett held
a number of positions with the Lederle Laboratories division of American
Cyanamid including Vice President, Cardiovascular Marketing.

         MARY E. PETIT was employed by the Company in January 1995 as Vice
President, Quality. In September 1996, Dr. Petit was elected to the position of
Senior Vice President-Operations. From June 1992 to January 1995, Dr. Petit was
Vice President, Quality Management with the Lederle Laboratories division of
American Cyanamid. Dr. Petit held positions of increasing responsibility during
her 12 year tenure with Lederle.

         SALAH U. AHMED was employed by the Company as Director of Research and
Development in 1993. Dr. Ahmed was named Vice President, Product Development in
September 1996. Before joining Barr, Dr. Ahmed was a Senior Scientist with
Forest Laboratories, Inc. from 1989 to 1993.

         EZZELDIN A. HAMZA was employed by the Company in July 1984 as Director
of Quality Control and thereafter, from August 1987, served as Director of
Scientific Affairs. In December 1988, Mr. Hamza was elected to the position of
Vice President-Technical Affairs. In 1993, he was elected Vice
President-Research and Development.

         CATHERINE F. HIGGINS was employed by the Company in January 1992 as
Vice President-Human Resources and was elected an officer in September 1992.
From June 1985 to December 1991, Ms. Higgins served as Vice President-Human
Resources for Inspiration Resources Corporation.

         WILLIAM T. MCKEE was employed by the Company in January 1995 as
Director of Finance and was appointed Treasurer in March 1995. In September 1996
Mr. McKee was elected to the position of Chief Financial Officer, and in
December 1997 Mr. McKee was elected Vice President. Prior to joining the
Company, Mr. McKee served as Vice President-Finance for Absolute Entertainment
Inc. From September 1983 through June 1993, Mr. McKee held management positions
in the accounting firms of Deloitte & Touche LLP and Gramkow & Carnevale, CPAs.
Mr. McKee is a C.P.A.

         GERALD F. PRICE was employed by the Company in January 1990 as Vice
President, Manufacturing and Engineering. He was elected an officer of the
Company in January 1990. Prior to assuming these positions, he served as Group
Vice President-Operations of Del Laboratories.

The Company's directors and executive officers are elected annually to serve
until the next annual meeting or until their successors have been elected and
qualified. The directors of the Company and their business experience are set
forth in the section headed "Information on Nominees" of the Company's Notice of
Annual Meeting of Shareholders, dated October 22, 1998 (the "Proxy Statement")
and are incorporated herein by reference.


                                                                              14
<PAGE>   15

ITEM 11. EXECUTIVE COMPENSATION

A description of the compensation of the Company's executive officers is set
forth in the sections headed "Executive Compensation", "Option Grants", "Option
Exercises and Option Values" and "Executive Agreements" of the Proxy Statement
and is incorporated herein by reference.

ITEM 12. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

A description of the security ownership of certain beneficial owners and
management is set forth in the sections headed "Ownership of Securities" and
"Changes in Control" of the Proxy Statement and is incorporated herein by
reference.

ITEM 13. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

A description of certain relationships and related transactions is set forth in
the section headed "Certain Relationships and Related Transactions" of the Proxy
Statement and is incorporated herein by reference.


                                                                              15
<PAGE>   16

                                     PART IV

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

(a)      Financial Statement Schedules:

         The consolidated balance sheets as of June 30, 1998 and 1997, and the
         related consolidated statements of operations, shareholders' equity and
         cash flows for each of the three years in the period ended June 30,
         1998 and the related notes to the consolidated financial statements,
         together with the Independent Auditors' Report, are incorporated herein
         by reference. With the exception of the aforementioned information and
         the information incorporated by reference in Items 5 through 8, the
         Annual Report is not deemed filed as part of this report. The following
         additional financial data should be read in conjunction with the
         financial statements in the Annual Report. All other schedules are
         omitted because they are not applicable or the required information is
         shown in the consolidated financial statements or notes.

                                                                            Page
         Independent Auditors' Report                                        20
         Financial Statement Schedule:
           II Valuation and Qualifying Accounts                              21

Exhibits

3.1      Restated Certificate of Incorporation of the Registrant

3.2      Amended and Restated By-Laws of the Registrant(1)

4.1      Loan and Security Agreement dated April 12, 1996 (9)

4.2      Amended and Restated Loan Agreement dated November 18, 1997 (9)

4.3      Note Purchase Agreements dated November 18, 1997 (1)

10.1     Stock Option Plan (3)

10.2     Savings and Retirement Plan  (8)

10.3     Economic Development Bond Financing Agreement, dated December 19, 1984,
         relating to 265 Livingston Street (2)

10.6     Collective Bargaining Agreement, effective April 1, 1996 (4)

10.7     Agreement with Bruce L. Downey (4)

10.8     Agreement with Ezzeldin A. Hamza (4)


                                                                              16
<PAGE>   17

10.9     Distribution and Supply Agreement for Tamoxifen Citrate dated March
         8, 1993 (4)

10.10    1993 Stock Incentive Plan (5)

10.11    1993 Employee Stock Purchase Plan (6)

10.12    1993 Stock Option Plan for Non-Employee Directors (7)

10.13    Agreement with Edwin A. Cohen and Amendment thereto (8)

10.14    Distribution and Supply Agreement for Ciprofloxacin Hydrochloride
         dated January 1997 (10)

13.0     1998 Annual Report to Shareholders

21.0     Subsidiaries of the Company (11)

23.0     Consent of Deloitte & Touche LLP

27.0     Financial Data Schedule

(1)      Previously filed with the Securities and Exchange Commission as an
         Exhibit to the Registrant's Quarterly Report on Form 10-Q for the
         quarter ended December 31, 1997 and incorporated herein by reference.

(2)      Previously filed with the Securities and Exchange Commission as an
         Exhibit to the Registrant's Annual Report on Form 10-K for the year
         ended June 30, 1986 and incorporated herein by reference.

(3)      Previously filed with the Securities and Exchange Commission as an
         Exhibit to the Registrant's Registration Statement on Form S-1 No.
         33-13472 and incorporated herein by reference.

(4)      Previously filed with the Securities and Exchange Commission as an
         Exhibit to the Registrant's Annual Report on Form 10-K for the year
         ended June 30, 1993 and incorporated herein by reference.

(5)      Previously filed with the Securities and Exchange Commission as an
         Exhibit to the Registrant's Registration Statement on Form S-8 Nos.
         33-73696 and 333-17349 and incorporated herein by reference.

(6)      Previously filed with the Securities and Exchange Commission as an
         Exhibit to the Registrant's Registration Statement on Form S-8 No.
         33-73700 and incorporated herein by reference.

(7)      Previously filed with the Securities and Exchange Commission as an
         Exhibit to the Registrant's Registration Statement on Form S-8 Nos.
         33-73698 and 333-17351 incorporated herein by reference.


                                                                              17
<PAGE>   18

(8)      Previously filed with the Securities and Exchange Commission as an
         Exhibit to the Registrant's Annual Report on Form 10-K for the year
         ended June 30, 1995 and incorporated herein by reference.

(9)      The Registrant agrees to furnish to the Securities and Exchange
         Commission, upon request, a copy of any instrument defining the rights
         of the holders of its long-term debt wherein the total amount of
         securities authorized thereunder does not exceed 10% of the total
         assets of the Registrant and its subsidiaries on a consolidated basis.

(10)     Previously filed with the Securities and Exchange Commission as an
         Exhibit to the Registrant's Quarterly Report on Form 10-Q for the
         quarter ended March 31, 1997 and incorporated herein by reference.

(11)     Previously filed with the Securities and Exchange Commission as an
         Exhibit to the Registrant's Annual Report on Form 10-K for the year
         ended June 30, 1988 and incorporated herein by reference.

(b)   Reports on Form 8-K

      None.


                                                                              18
<PAGE>   19

                                   SIGNATURES

         Pursuant to the requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, the Registrant has duly caused this report to be signed on
its behalf by the undersigned thereunto duly authorized.

                             BARR LABORATORIES, INC.

        Signature                    Title                      Date

BY BRUCE L. DOWNEY         Chairman of the Board,         September 9, 1998
  (Bruce L. Downey)        Chief Executive Officer & President

BY WILLIAM T. MCKEE        Vice President, Chief          September 9, 1998
  (William T. McKee)       Financial Officer & Treasurer

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

        Signature                    Title                      Date

BRUCE L. DOWNEY            Chairman of the Board,         September 9, 1998
(Bruce L. Downey)          Chief Executive Officer &
                           President

EDWIN A. COHEN             Vice Chairman of the Board     September 9, 1998
(Edwin A. Cohen)

PAUL M. BISARO             Director                       September 9, 1998
(Paul  M. Bisaro)

ROBERT J. BOLGER           Director                       September 9, 1998
(Robert J. Bolger)

MICHAEL F. FLORENCE        Director                       September 9, 1998
(Michael F. Florence)

JACOB M. KAY               Director                       September 9, 1998
(Jacob M. Kay)

BERNARD C. SHERMAN         Director                       September 9, 1998
(Bernard C. Sherman)

GEORGE P. STEPHAN          Director                       September 9, 1998
(George P. Stephan)


                                                                              19
<PAGE>   20

INDEPENDENT AUDITORS' REPORT

To the Board of Directors and Shareholders of
  Barr Laboratories, Inc.:

We have audited the financial statements of Barr Laboratories, Inc. and
subsidiaries (the "Company") as of June 30, 1998 and 1997, and for each of the
three years in the period ended June 30, 1998, and have issued our report
thereon dated August 19, 1998; such financial statements and report are included
in your June 30, 1998 Annual Report to Shareholders and are incorporated herein
by reference. Our audits also included the financial statement schedule of Barr
Laboratories, Inc., listed in Item 14. This financial statement schedule is the
responsibility of the Company's management. Our responsibility is to express an
opinion based on our audits. In our opinion, such financial statement schedule,
when considered in relation to the basic financial statements taken as a whole,
presents fairly in all material respects the information set forth therein.

DELOITTE & TOUCHE LLP

Parsippany, New Jersey
August 19, 1998


                                                                              20
<PAGE>   21

                                                                     SCHEDULE II

BARR LABORATORIES, INC.
VALUATION AND QUALIFYING ACCOUNTS
YEARS ENDED JUNE 30, 1998, 1997 AND 1996

<TABLE>
<CAPTION>
                                         BALANCE AT    ADDITIONS,  RECOVERY
                                        BEGINNING OF   COSTS AND    AGAINST     DEDUCTIONS,  BALANCE AT
                                           YEAR        EXPENSE     WRITE-OFFS   WRITE-OFFS   END OF YEAR
                                           ----        -------     ----------   ----------   -----------
<S>                                     <C>            <C>         <C>          <C>          <C>   
Allowance for doubtful accounts:
  Year ended June 30, 1996                $  400       $   95       $    2       $  305       $  192
  Year ended June 30, 1997                   192          735           22          679          270
  Year ended June 30, 1998                   270          180            1          189          262

Reserve for returns and allowances:
  Year ended June 30, 1996                 1,700        5,114         --          5,207        1,607
  Year ended June 30, 1997                 1,607        5,105         --          5,362        1,350
  Year ended June 30, 1998                 1,350        5,003         --          3,877        2,476

Inventory reserves:
  Year ended June 30, 1996                 3,550        2,359         --          4,630        1,279
  Year ended June 30, 1997                 1,279        5,334         --          2,978        3,635
  Year ended June 30, 1998                 3,635        8,043         --          6,103        5,575
</TABLE>


                                                                              21
<PAGE>   22
                                Exhibit Index

Exhibits                         Description
--------                         -----------

3.1      Restated Certificate of Incorporation of the Registrant

3.2      Amended and Restated By-Laws of the Registrant(1)

4.1      Loan and Security Agreement dated April 12, 1996 (9)

4.2      Amended and Restated Loan Agreement dated November 18, 1997 (9)

4.3      Note Purchase Agreements dated November 18, 1997 (1)

10.1     Stock Option Plan (3)

10.2     Savings and Retirement Plan  (8)

10.3     Economic Development Bond Financing Agreement, dated December 19, 1984,
         relating to 265 Livingston Street (2)

10.6     Collective Bargaining Agreement, effective April 1, 1996 (4)

10.7     Agreement with Bruce L. Downey (4)

10.8     Agreement with Ezzeldin A. Hamza (4)

10.9     Distribution and Supply Agreement for Tamoxifen Citrate dated March
         8, 1993 (4)

10.10    1993 Stock Incentive Plan (5)

10.11    1993 Employee Stock Purchase Plan (6)

10.12    1993 Stock Option Plan for Non-Employee Directors (7)

10.13    Agreement with Edwin A. Cohen and Amendment thereto (8)

10.14    Distribution and Supply Agreement for Ciprofloxacin Hydrochloride
         dated January 1997 (10)

13.0     1998 Annual Report to Shareholders

21.0     Subsidiaries of the Company (11)

23.0     Consent of Deloitte & Touche LLP

27.0     Financial Data Schedule

(1)      Previously filed with the Securities and Exchange Commission as an
         Exhibit to the Registrant's Quarterly Report on Form 10-Q for the
         quarter ended December 31, 1997 and incorporated herein by reference.

(2)      Previously filed with the Securities and Exchange Commission as an
         Exhibit to the Registrant's Annual Report on Form 10-K for the year
         ended June 30, 1986 and incorporated herein by reference.

(3)      Previously filed with the Securities and Exchange Commission as an
         Exhibit to the Registrant's Registration Statement on Form S-1 No.
         33-13472 and incorporated herein by reference.

(4)      Previously filed with the Securities and Exchange Commission as an
         Exhibit to the Registrant's Annual Report on Form 10-K for the year
         ended June 30, 1993 and incorporated herein by reference.

(5)      Previously filed with the Securities and Exchange Commission as an
         Exhibit to the Registrant's Registration Statement on Form S-8 Nos.
         33-73696 and 333-17349 and incorporated herein by reference.

(6)      Previously filed with the Securities and Exchange Commission as an
         Exhibit to the Registrant's Registration Statement on Form S-8 No.
         33-73700 and incorporated herein by reference.

(7)      Previously filed with the Securities and Exchange Commission as an
         Exhibit to the Registrant's Registration Statement on Form S-8 Nos.
         33-73698 and 333-17351 incorporated herein by reference.           

(8)      Previously filed with the Securities and Exchange Commission as an
         Exhibit to the Registrant's Annual Report on Form 10-K for the year
         ended June 30, 1995 and incorporated herein by reference.

(9)      The Registrant agrees to furnish to the Securities and Exchange
         Commission, upon request, a copy of any instrument defining the rights
         of the holders of its long-term debt wherein the total amount of
         securities authorized thereunder does not exceed 10% of the total
         assets of the Registrant and its subsidiaries on a consolidated basis.

(10)     Previously filed with the Securities and Exchange Commission as an
         Exhibit to the Registrant's Quarterly Report on Form 10-Q for the
         quarter ended March 31, 1997 and incorporated herein by reference.

(11)     Previously filed with the Securities and Exchange Commission as an
         Exhibit to the Registrant's Annual Report on Form 10-K for the year
         ended June 30, 1988 and incorporated herein by reference.