Document:

EXHIBIT 10.16
                      THE AMERICAN INSTITUTE OF ARCHITECHTS

AIA Document A111

             Standard Form of Agreement Between Owner and Contractor
                        where the basis of payment is the
                           COST OF THE WORK PLUS A FEE
                   with or without a Guaranteed Maximum Price

                                  1987 EDITION

THIS DOCUMENT HAS IMPORTANT LEGAL CONSEQUENCES; CONSULTATION WITH AN ATTORNEY IS
           ENCOURAGED WITH RESPECT TO ITS COMPLETION OR MODIFICATION.

    The 1987 Edition of AIA Document A201, General Conditions of the Contract
  for Construction, is adopted in this document by reference. Do not use with
           other general conditions unless this document is modified.

     This document has been approved and endorsed by The Associated General
                            Contractors of America.

--------------------------------------------------------------------------------
      AGREEMENT

      made as of the Thirty-first day of January, in the year of Two Thousand
Two

      BETWEEN the Owner:                       RepliGen Corporation
      (Name and address)                       117 Fourth Avenue
                                               Needham, MA  02494

      and the Contractor:                      Siena Construction Corporation
      (Name and address)                       17 Tudor Street
                                               Cambridge, MA  02139

      the Project is:                          RepliGen
      (Name and address)                       41 Seyon Street; Building 1
                                               Waltham, MA

      the Architect is:                        Olson Lewis & Dioli Architects
      (Name and address)                       17 Elm Street
                                               Manchester-By-The-Sea, MA  01944

The Owner and Contractor agree as set forth below.

      Copyright 1920, 1925, 1951, 1958, 1961, 1963, 1967, 1974, 1978, (C)1987 by
The American Institute of Architects, 1735 New York Avenue, N.W., Washington,
D.C. 20006. Reproduction of the material herein or substantial quotation of its
provisions without written permission of the AIA violates the copyright laws of
the United States and will be subject to legal prosecution.

--------------------------------------------------------------------------------
AIA DOCUMENT A111 - OWNER-CONTRACTOR AGREEMENT - TENTH EDITION - AIA -(C)1987
THE AMERICAN INSTITUTE OF ARCHITECTS, 1735 NEW YORK AVENUE, N.W., WASHINGTON,
D.C. 20006                                                           A113-1987 2

<PAGE>

                                    ARTICLE 1
                             THE CONTRACT DOCUMENTS

1.1 The Contract Documents consist of this Agreement, Conditions of the Contract
(General, Supplementary and other Conditions), Drawings, Specifications, Addenda
issued prior to execution of this Agreement, other documents listed in this
Agreement and Modifications issued after execution of this Agreement; these form
the Contract, and are as fully a part of the Contract as if attached to this
Agreement or repeated herein. The Contract represents the entire and integrated
agreement between the parties hereto and supersedes prior negotiations,
representations or agreements, either written or oral. An enumeration of the
Contract Documents, other than Modifications, appears in Article 16. If anything
in the other Contract Documents is inconsistent with this Agreement, this
Agreement shall govern.

                                    ARTICLE 2
                            THE WORK OF THIS CONTRACT

2.1 The Contractor shall execute the entire Work described in the Contact
Documents, except to the extent specifically indicated in the Contract Documents
to be the responsibility of others, or as follows:

The Work of this Contract work is work only within the demising walls of
Repligen or as otherwise noted on Contract Documents.

The Work of this Contract includes "Design/Build" responsibility for Plumbing,
Fire Protection, HVAC and Electrical Systems. The basis for design of these
systems will be from information provided by Repligen Corporation.

                                    ARTICLE 3
                           RELATIONSHIP OF THE PARTIES

3.1 The Contractor accepts the relationship of trust and confidence established
by this Agreement and covenants with the Owner to cooperate with the Architect
and utilize the Contractor's best skill, efforts and judgment in furthering the
interests of the Owner; to furnish efficient business administration and
supervision; to make best efforts to furnish at all times an adequate supply of
workers and materials; and to perform the Work in the best way and most
expeditious and economical manner consistent with the interests of the Owner.
The Owner agrees to exercise best efforts to enable the Contractor to perform
the Work in the best way and most expeditious manner by furnishing and approving
in a timely way information required by the Contractor and making payments to
the Contractor in accordance with requirements of the Contract Documents.

<PAGE>

                                    ARTICLE 4
                 DATE OF COMMENCEMENT AND SUBSTANTIAL COMPLETION

4.1 The date of commencement is the date from which the Contract Time of
Subparagraph 4.2 is measured; it shall be the date of this Agreement, as first
written above, unless a different date is stated below or provision is made for
the date to be fixed in a notice to proceed issued by the Owner.

(Insert the date of commencement, if it differs from the date of this Agreement
or, if applicable, state that the date will be fixed in a notice to proceed.)

Unless the date of commencement is established by a notice to proceed issued by
the Owner, the Contractor shall notify the Owner in writing not less than five
days before commencing the Work to permit the timely filing of mortgages,
mechanic's liens and other security interests.

4.2 The Contractor shall achieve Substantial Completion of the entire Work not
later than

(Insert the calendar date or number op calendar days after the date of
commencement. Also insert any requirements for earlier Substantial Completion of
certain portions of the Work, if not stated elsewhere in the Contract
Documents.)

April 30, 2002,

, subject to adjustments of this Contract Time as provided in the Contract
Documents.

(insert provisions, if any, for liquidated damages relating to failure to
complete on time.)

                                    ARTICLE 5
                                  CONTRACT SUM

5.1 The Owner shall pay the Contractor in current funds for the Contractor's
performance of the Contract the Contract Sum consisting of the Cost of the Work
as defined in Article 7 and the Contractor's Fee determined as follows:

(Stale a lump sum, percentage of Cost of the Work or other provisions for
determining the Contractor's Fee and explain how the Contractor's Fee is to be
adjusted for changes in the Work.) Contractor's Fee shall be 3% of the total
direct costs.

5.2 GUARANTEEING MAXIMUM PRICE (IF APPLICABLE)

5.2.1 The sum of the Cost of the Work and the Contractor's Fee is guaranteed by
the Contractor not to exceed

One Million, nine hundred twenty four thousand Dollars ($1,924,000)

<PAGE>

subject to additions and deductions by Change Order as provided in the Contract
Documents. Such maximum sum is referred to in the Contract Documents as the
Guaranteed Maximum Price. Costs which would cause the Guaranteed Maximum Price
to be exceeded shall be paid by the Contractor without reimbursement by the
Owner.

(Insert specific provisions if the Contractor is to participate in any savings.)

All savings shall be returned to RepliGen Corporation.

Fixed General Conditions shall be $163,000.00.

5.2.2 The Guaranteed Maximum Price is based upon the following alternates, if
any, which are described in the Contract Documents and are hereby accepted by
the Owner:

(State the numbers or other identification of accepted alternates, but only if a
Guaranteed Maximum Price is inserted in Subparagraph 5.2.1. If decisions on
other alternates are to be made by the Owner subsequent to the execution of this
Agreement, attach a schedule of such other alternates showing the amount for
each and the date until which that amount is valid.)

See Attached Exhibit C

5.2.3 The amounts agreed to for unit prices, if any, are as follows: (State unit
prices only if a Guaranteed maximum Price is inserted in Subparagraph 5.2.1.)

N/A

                                    ARTICLE 6
                               CHANGES IN THE WORK

6.1 CONTRACTS WITH A GUARANTEED MAXIMUM PRICE

6.1.1 Adjustments to the Guaranteed Maximum Price on account of changes in the
Work may be determined by any of the methods listed in Subparagraph 7.3.3 of the
General Conditions.

6.1.2 In calculating adjustments to subcontracts (except those awarded with the
Owner's prior consent on the basis of cost plus a fee), the terms "cost" and
"fee" as used in Clause 7.3.3.3 of the General Conditions and the terms "costs"
and "a reasonable allowance for overhead and profit" as used in Subparagraph
7.3.6 of the General Conditions shall have the meanings assigned to them in the
General Conditions and shall not be modified by Articles 5, 7 and 8 of this
Agreement. Adjustments to subcontracts awarded with the Owner's prior consent on
the basis of cost plus a fee shall be calculated in accordance with the terms of
those subcontracts.

<PAGE>

6.1.3 In calculating adjustments to this Contract, the terms "cost" and "costs"
as used in the above-referenced provisions of the General Conditions shall mean
the Cost of the Work as defined in Article 7 of this Agreement and the terms
"fee" and "a reasonable allowance for overhead and profit" shall mean the
Contractor's Fee as defined in Paragraph 5.1 of this Agreement.

6.2 CONTRACTS WITHOUT A GUARANTEED MAXIMUM PRICE

6.2.1 Increased costs for the items set forth in Article 7 which result from
changes in the Work shall become part of the Cost of the Work, and the
Contractor's Fee shall be adjusted as provided in Paragraph 5.1.

6.3 ALL CONTRACTS

6.3.1 If no specific provision is made in Paragraph 5.1 for adjustment of the
Contractor's Fee in the case of changes in the Work, or if the extent of such
changes is such, in the aggregate, that application of the adjustment provisions
of Paragraph 5.1 will cause substantial inequity to the Owner or Contractor, the
Contractor's Fee shall be equitably adjusted on the basis of the Fee established
for the original Work.

                                    ARTICLE 7
                             COSTS TO BE REIMBURSED

7.1 The term Cost of the Work shall mean costs necessarily incurred by the
Contractor in the proper performance of the Work. Such costs shall be at rates
not higher than the standard paid at the place of the Project except with prior
consent of the Owner. The Cost of the Work shall include only the items set
forth in this Article 7.

7.1.1 LABOR COSTS

7.1.1.1 Wages per Siena Construction Standard Reimbursable Rates attached as
Exhibit 'A' of construction workers directly employed by the Contractor to
perform the construction of the Work at the site or, with the Owner's agreement,
at off-site workshops.

7.1.1.2 Wages per Siena Construction Standard Reimbursable Rates attached as
Exhibit 'A' or salaries of the Contractor's supervisory and administrative
personnel when stationed at the site with the Owner's agreement.

(If it is intended that the wages or salaries of certain personnel stationed at
the Contractor's principal or other offices shall be included in the Cost of the
Work, identify in Article 14 the personnel to be included and whether for all or
only part of their time.)

7.1.1.3 Wages and salaries per Siena Construction Standard Reimbursable Rates
attached as Exhibit `A" the Contractor's supervisory or administrative personnel
engaged, at factories, workshops or on the road,

<PAGE>

in expediting the production or transportation of materials or equipment
required for the Work, but only for that portion of their time required for the
Work.

7.1.1.4 Costs paid or incurred by the Contractor for taxes, insurance,
contributions, assessments and benefits required by law or collective bargaining
agreements and, for personnel not covered by such agreements, customary benefits
such as sick leave, medical and health benefits, holidays, vacations and
pensions, provided such costs are based on wages and salaries included in the
Cost of the Work under Clauses 7.1.1.1 through 7.1.1.3. per Siena Construction
Standard Reimbursable Rates attached as Exhibit 'A'

7.1.2 SUBCONTRACT COSTS

Payments made by the Contractor to Subcontractors in accordance with the
requirements of the subcontracts.

7.1.3 COSTS OF MATERIALS AND EQUIPMENT INCORPORATED IN THE COMPLETED
CONSTRUCTION

7.1.3.1 Costs, including transportation, of materials and equipment incorporated
or to be incorporated in the completed construction.

7.1.3.2 Costs of materials described in the preceding Clause 7.1.3.1 in excess
of those actually installed but required to provide reasonable allowance for
waste and for spoilage. Unused excess materials, if any, shall be handed over to
the Owner at the completion of the Work or, at the Owner's option, shall be sold
by the Contractor; amounts realized, if any, from such sales shall be credited
to the Owner as a deduction from the Cost of the Work.

7.1.4 COSTS OF OTHER MATERIALS AND EQUIPMENT, TEMPORARY FACILITIES AND RELATED
ITEMS

7.1.4.1 Costs, including transportation, installation, maintenance, dismantling
and removal of materials, supplies, temporary facilities, machinery, equipment,
and hand tools not customarily owned by the construction workers, which are
provided by the Contractor at the site and fully consumed in the performance of
the Work; and cost less salvage value on such items if not fully consumed,
whether sold to others or retained by the Contractor. Cost for items previously
used by the Contractor shall mean fair market value.

7.1.4.2 Rental charges for temporary facilities, machinery, equipment, and hand
tolls not customarily owned by the construction workers, which are provided by
the Contractor at the site, whether rented from the Contractor or others, and
costs of transportation, installation, minor repairs and replacements,
dismantling and removal thereof. Rates and quantities of equipment rented shall
be subject to the Owner's prior approval.

7.1.4.3 Costs of removal of debris from the site.

<PAGE>

7.1.4.4 Costs of telegrams and long-distance telephone calls, postage and parcel
delivery charges, telephone service at the site and reasonable petty cash
expenses of the site office.

7.1.4.5 That portion of the reasonable travel and subsistence expenses of the
Contractor's personnel incurred while traveling in discharge of duties connected
with the Work.

7.1.5 MISCELLANEOUS COSTS

7.1.5.1 That portion directly attributable to this Contact of premiums for
insurance and bonds.

7.1.5.2 Sales, use or similar taxes imposed by a governmental authority which
are related to the Work and for which the Contractor is liable.

7.1.5.3 Fees and assessments for the building permit and for other permits,
licenses and inspections for which the Contractor is required by the Contract
Documents to pay.

7.1.5.4 Fees of testing laboratories for tests required by the Contract
Documents, except those related to defective or nonconforming Work for which
reimbursement is excluded by Subparagraph 13.5.3 of the General Conditions or
other provisions of the Contract Documents and which do not fall within the
scope of Subparagraphs 7.2.2 through 7.2.4 below.

7.1.5.5 Royalties and license fees paid for the use of a particular design,
process or product required by the Contract Documents; the cost of defending
suits or claims for infringement of patent rights arising from such requirement
by the Contract Documents; payments made in accordance with legal judgments
against the Contractor resulting from such suits or claims and payments of
settlements made with the Owner's consent; provided, however, that such costs of
legal defenses, judgment and settlements shall not be included in the
calculation of the Contractor's Fee or of a Guaranteed Maximum Price, if any,
and provided that such royalties, fees and costs are not excluded by the last
sentence of Subparagraph 3.17.1 of the General Conditions or other provisions of
the Contract Documents.

7.1.5.6 Deposits lost for causes other than the Contractor's fault or
negligence.

7.1.6 OTHER COSTS

7.1.6.1 Other costs incurred in the performance of the Work if and to the extent
approved in advance in writing by the Owner.

7.2 EMERGENCIES: REPAIRS TO DAMAGED, DEFECTIVE OR NONCONFORMING WORK The Cost of
the Work shall also include costs described in Paragraph 7.1 which are incurred
by the Contractor:

<PAGE>

7.2.1 In taking action to prevent threatened damage, injury or loss in case of
an emergency affecting the safety of persons and property, as provided in
Paragraph 10.3 of the General Conditions.

7.2.2 In repairing or correcting Work danged or improperly executed by
construction workers in the employ of the Contractor, provided such damage or
improper execution did not result from the fault or negligence of the Contractor
or the Contractor's foremen, engineers or superintendents, of other supervisory,
administrative or managerial personnel of the Contractor.

7.2.3 In repairing damaged Work other than that described in Subparagraph 7.2.2,
provided such damage did not result from the fault or negligence of the
Contractor or the Contractor's personnel, and only to the extent that the cost
of such repairs is not recoverable by the Contractor from others and the
Contractor is not compensated therefore by insurance or otherwise.

7.2.4 In correcting defective or nonconforming Work performed or supplied by a
Subcontractor or material supplier and not corrected by them, provided such
defective or nonconforming Work did nor result from the fault or neglect of the
Contractor or the Contractor's personnel adequately to supervise and direct the
Work of the Subcontractor or material supplier, and only to the extent that the
cost of correcting the defective or nonconforming Work is not recoverable by the
Contractor from the Subcontractor or material supplier.

                                    ARTICLE 8
                           COSTS NOT TO BE REIMBURSED

8.1 The Cost of the Work shall not include:

8.1.1 Salaries and other compensation of the Contractor's personnel stationed at
the Contractor's principal office or offices other than the site office, except
as specifically provided in Clauses 7.1.1.2 and 7.1.1.3 or as may be provided in
Article 14.

8.1.2 Expenses of the Contractor's principal office and offices other than the
site office.

8.1.3 Overhead and general expenses, except as may be expressly included in
Article 7.

8.1.4 The Contractor's capital expenses, including interest on the Contractor's
capital employed for the Work.

8.1.5 Rental costs of machinery and equipment, except as specifically provided
in Clause 7.1.4.2.

8.1.6 Except as provided in Subparagraphs 7.2.2 through 7.2.4 and Paragraph 13.5
of this Agreement, costs due to the fault or negligence of the Contractor,
Subcontractors, anyone directly or indirectly employed by any of them, or for
whose acts any of them may be liable, including but not limited to costs for the
correction of damaged, defective or nonconforming Work, disposal and replacement
of materials

<PAGE>

and equipment incorrectly ordered or supplied, and making good damage to
property not forming part of the Work.

8.1.7 Any cost not specifically and expressly described in Article 7.

8.1.8 Costs which would cause the Guaranteed Maximum Price, if any, to be
exceeded.

                                    ARTICLE 9
                         DISCOUNTS, REBATES AND REFUNDS

9.1 Cash discounts obtained on payments made by the Contractor shall accrue to
the Owner if (1) before making the payment, the Contractor included them in an
Application for Payment and received payment therefore from the Owner, or (2)
the Owner has deposited funds with the Contractor with which to make payments;
otherwise, cash discounts shall accrue to the Contractor. Trade discounts,
rebates, refunds and amounts received from sales of surplus materials and
equipment shall accrue to the Owner, and the Contractor shall make provisions so
that they can be secured.

9.2 Amounts which accrue to the Owner in accordance with the provisions of
Paragraph 9.1 shall be credited to the Owner as a deduction from the Cost of the
Work

                                   ARTICLE 10
                        SUBCONTRACTS AN0 OTHER AGREEMENTS

10.1 Those portions of the Work that the Contractor does not customarily perform
with the Contractor's own personnel shall be performed under subcontracts or by
other appropriate agreements with the Contractor. The Contractor shall obtain
bids from subcontractors and from suppliers of materials or equipment fabricated
especially for the Work and shall deliver such bids to the Architect. The Owner
will then determine, with the advice of the Contractor and subject to the
reasonable objection of the Architect, which bids will be accepted. The Owner
may designate specific persons or entities from whom the Contractor shall obtain
bids; however, if a Guaranteed Maximum Price has been established, the Owner may
not prohibit the Contractor from obtaining bids from others. The Contractor
shall not be required to contract with anyone to whom the Contractor has
reasonable objection.

10.2 If a Guaranteed Maximum Price has been established and a bidder among those
whose bids are delivered by the Contractor to the Architect (1) is recommended
to the Owner by the Contractor, (2) is qualified to perform that portion of the
Work; and (3) has submitted a bid which conforms to the requirements of the
Contract Documents without reservations or exceptions, but the Owner requires
that another bid be accepted; then the Contractor may require that a Change
Order be issued to adjust the Guaranteed Maximum Price by the difference between
the bid of the person or entity recommended to the Owner by the Contractor and
the amount of the subcontract or other agreement actually signed with the person
or entity designated by the Owner.

<PAGE>

10.3 Subcontracts or other agreements shall conform to the payment provisions of
Paragraphs 12.7 and 12.8, and shall not be awarded on the basis of cost plus a
fee without the prior consent of the Owner.

                                   ARTICLE 11
                               ACCOUNTING RECORDS

11.1 The Contractor shall keep full and detailed accounts and exercise such
controls as may be necessary for proper financial management under this
Contract; the accounting and control systems shall be satisfactory to the Owner.
The Owner and the Owner's accountants shall be afforded access to the
Contractor's records, books, correspondence, instructions, drawings, receipts,
subcontracts, purchase orders, vouchers, memoranda and other data relating to
this Contract, and the Contractor shall preserve these for a period of three
years after final payment, or for such longer period as may be required by law.

                                   ARTICLE 12
                                PROGRESS PAYMENTS

12.1 Based upon Applications for Payment submitted to the Architect by the
Contractor and Certificates for Payment issued by the Architect, the Owner shall
make progress payments on account of the Contract Sum to the Contractor as
provided below and elsewhere in the Contract Documents.

12.2 The period covered by each Application for Payment shall be one calendar
month ending on the last day of the month, or as follows:

12.3 Provided an Application for Payment is approved by the Architect not later
than the Fifth day of the month, the Owner shall make payment to the Contractor
no later than 30 days. If an Application for Payment is approved by the
Architect after the application date fixed above, payment shall be made by the
Owner not later than 30 days after the Architect receives the Application for
Payment. Approval shall not be unreasonably withheld.

12.4 With each Application for Payment the Contractor shall submit payrolls,
petty cash accounts, receipted invoices or invoices with check vouchers
attached, and any other evidence required by the Owner or Architect to
demonstrate that cash disbursements already made by the Contractor on account of
the Cost of the Work equal or exceed (1) progress payments already received by
the Contractor; less (2) that portion of those payments attributable to the
Contractor's Fee; plus (3) payrolls for the period covered by the present
Application for Payment; plus (4) retainage provided in Subparagraph 12.5.4, if
any, applicable to prior progress payments.

12.5 CONTRACTS WITH A GUARANTEED MAXIMUM PRICE

12.5.1 Each Application for Payment shall be based upon the most recent schedule
of values submitted by the Contractor in accordance with the Contract Documents.
The schedule of values shall allocate the entire Guaranteed Maximum Price among
the various portions of the Work, except that the Contractor's Fee shall be
shown as a single separate item. The schedule of values shall be prepared in
such form and

<PAGE>

supported by such data to substantiate its accuracy as the Architect may
require. This schedule, unless objected to by the Architect, shall be used as a
basis for reviewing the Contractor's Applications for Payment.

12.5.2 Applications for Payment shall show the percentage completion of each
portion of the Work as of the end of the period covered by the Application for
Payment. The percentage completion shall be the lesser of (1) the percentage of
that portion of the Work which has actually been completed or (2) the percentage
obtained by dividing (a) the expense which has actually been incurred by the
Contractor on account of that portion of the Work for which the Contractor has
made or intends to make actual payment prior to the next Application for Payment
by (b) the share of the Guaranteed Maximum Price allocated to that portion of
the Work in the schedule of values.

12.5.3 Subject to other provisions of the Contract Documents, the amount of each
progress payment shall be reputed as follows:

12.5.3.1 Take that portion of the Guaranteed Maximum Price properly allocable to
completed Work as determined by multiplying the percentage completion of each
portion of the Work by the share of the Guaranteed Maximum Price allocated to
that portion of the Work in the schedule of values. Pending final determination
of cost to the Owner of changes in the Work, amounts not in dispute may be
included as provided in Subparagraph 7.3.7 of the General Conditions, even
though the Guaranteed Maximum Price has not yet been adjusted by Change Order.

12.5.3.2 Add that portion of the Guaranteed Maximum Price properly allocable to
materials and equipment delivered and suitably stored at the site for subsequent
incorporation in the Work or, if approved in advance by the Owner, suitably
stored off the site at a location agreed upon in writing.

12.5.3.3 Add the Contractor's Fee, less retainage of ten percent (10%). The
Contractor's Fee shall be computed upon the Cost of the Work described in the
two preceding Clauses at the rate stated in Paragraph 5.1 or, if the
Contractor's Fee is stated as a fixed sum in that Paragraph, shall be an amount
which bears the same ratio to that fixed-sum Fee as the Cost of the Work in the
two preceding Clauses bears to a reasonable estimate of the probable Cost of the
Work upon its completion.

12.5.3.4 Subtract the aggregate of previous payments made by the Owner.

l2.5.3.5 Subtract the shortfall, if any, indicated by the Contractor in the
documentation required by Paragraph 12.4 to substantiate prior Applications for
Payment, or resulting from errors subsequently discovered by the Owner's
accountants in such documentation.

12.5.3.6 Subtract amounts, if any, for which the Architect has withheld or
nullified a Certificate for Payment as provided in Paragraph 9.5 of the General
Conditions.

12.5.4 Additional retainage, if any, shall be as follows:

<PAGE>

(If it is intended to retain, additional amounts from progress payments to the
Contractor beyond (1) the retainage from the Contractor's Fee provided in Clause
12.5.3.3, (2) the retainage from Subcontractors provided in paragraph 12.7
below, and (3) the retainage, if any, provided by other provisions of the
Contract, insert provision for such additional retainage here. Such provision,
if made, should also describe any arrangement for limiting or reducing the
amount retained after the Work reaches a certain state of completion.

There shall be no retainage on materials purchased by Siena Construction
Corporation. Retainage of subcontractors who have completed their work and their
punch list work shall be reduced to O% thirty (30) days after completion of the
Work. After Substantial Completion retainage shall be reduced to reflect the
value of the punchlist work outstanding but in no event shal1 the retainage be
less than $10,000. Upon completion of the punchlist RepliGen will make final
payment.

12.6 CONTRACTS WITHOUT A GUARANTEED MAXIMUM PRICE
      Intentionally Deleted

12.7 Except with the Owner's prior approval, payments to Subcontractors included
in the Contractor's Applications for Payment shall not exceed an amount for each
Subcontractor calculated as follows:

12.7.1 Take that portion of the Subcontract Sum properly allocable to complete4
Work as determined by multiplying the percentage completion of each portion of
the Subcontractor's Work by the share of the total Subcontract Sum allocated to
that portion in the Subcontractor's schedule of values, less retainage of ten
percent (10%). Pending final determination of amounts to be paid to the
Subcontractor for changes in the Work, amounts not in dispute may be included as
provided in Subparagraph 7.3.7 of the General Conditions even though the
Subcontract Sum has not yet been adjusted by Change Order.

12.7.2 Add that portion of the Subcontract Sum properly allocable to materials
and equipment delivered and suitably stored at the site for subsequent
incorporation in the Work or, if approved in advance by the Owner, suitably
motored off the site at a location agreed upon in writing, less retainage of 10
percent (10%).

12.7.3 Subtract the aggregate of previous payments made by the Contractor to the
Subcontractor.

12.7.4 Subtract amounts, if any, for which the Architect has withheld or
nullified a Certificate for Payment by the Owner to the Con-tractor for reasons
which are the fault of the Subcontractor.

12.7.5 Add, upon Substantial Completion of the entire Work of the Contractor, a
sum sufficient to increase the total payments to the Subcontractor to percent ()
of the Subcontract Sum, less amounts, if any, for incomplete. Work and unsettled
claims; and, if final completion of the entire Work is thereafter materially
delayed through no fault of the Subcontractor, add any additional amounts
payable on account of Work of the Subcontractor in accordance with Subparagraph
9.10.3 of the General Conditions.

<PAGE>

(If it is intended, prior to Substantial Completion of the entire Work of the
Contractor, to reduce or limit the retainage from Subcontractors resulting from
the percentages inserted in Subparagraphs 12.7. I and 12.7.2 above, and this is
not explained elsewhere in the Contract Documents, insert here provisions for
such reduction or limitation.)

The Subcontract Sum is the total amount stipulated in the subcontract to be paid
by the Contractor to the Subcontractor for the Subcontractor's performance of
the subcontract.

12.8 Except with the Owner's prior approval, the Contractor shall nor make
advance payments to suppliers for materials or equipment which have not been
delivered and stored at the site.

12 9 In taking action on the Contractor's Applications for Payment, the
Architect shall be entitled to rely on the accuracy and completeness of the
information furnished by the Contractor and shall not be deemed to represent
that the Architect has made a detailed examination, audit or arithmetic
verification of the documentation submitted in accordance with Paragraph 12.4 or
other supporting data; that the Architect has made exhaustive or continuous
on-site inspections or that the Architect has made examinations to ascertain how
or for what purposes the Contractor has used amounts previously paid on account
of the Contract. Such examinations, audits and verifications, if required by the
Owner, will be performed by the Owner's accountants acting in the sole interest
of the Owner.

                                   ARTICLE 13
                                  FINAL PAYMENT

13.1 Final payment shall be made by the Owner to the Contractor when (1) the
Contract has been fully performed by the Contractor except for the Contractor's
responsibility to correct defective or nonconforming Work, as provided in
Subparagraph 12.2.2 of the General Conditions, and to satisfy other
requirements, if any, which necessarily survive final payment; (2) a final
Application for

payment and a final accounting for the Cost of the Work have been submitted by
the Contractor and reviewed by the Owner's accountants; and (3) a final
Certificate for Payment has then been issued by the Architect; such final
payment shall be made by the Owner not more than 30 days after the issuance of
the Architect's final Certificate for Payment, or as follows:

13.2 The amount of the final payment shall be calculated as follows:

13.2.1 Take the sum of the Cost of the Work substantiated by the Contractor's
final accounting and the Contractor's Fee; but nor more than the Guaranteed
Maximum Price, if any.

13.2.2 Subtract amounts, if any, for which the Architect withholds, in whole or
in part, a final Certificate for Payment as provided in Subparagraph 9.5.1 of
the General Conditions or other provisions of the Contract Documents.

<PAGE>

13.2.3 Subtract the aggregate of previous payments made by the Owner. If the
aggregate of previous payments made by the Owner exceeds the amount due the
Contractor, the Contractor shall reimburse the difference to the Owner.

13.3 The Owner's accountants will review and report in writing on the
Contractor's final accounting within 30 days after delivery of the final
accounting to the Architect by the Contractor. Based upon such Cost of the Work
as the Owner's accountants report to be substantiated by the Contractor's final
accounting, and provided the other conditions of Paragraph 13.1 have been met,
the Architect will, within seven days after receipt of the written report of the
Owner's accountants, either issue to the Owner a final Certificate for Payment
with a copy to the Contractor, or notify the Contractor and Owner in writing of
the Architect's reasons for withholding a certificate as provided in
Subparagraph 9.5.1 of the General Conditions. The time periods stated in this
Paragraph 13.3 supersede those stated in Subparagraph 9.4.1 of the General
Conditions.

13.4 If the Owner's accountants report the Cost of the Work as substantiated by
the Contractor's final accounting to be less than claimed by the Contractor, the
Contractor shall be entitled to demand arbitration of the disputed amount
without a further decision of the Architect. Such demand for arbitration shall
be made by the Contractor within 30 days after the Contractor's receipt of a
copy of the Architect's final Certificate for Payment; failure to demand
arbitration within this 30-day period shall result in the substantiated amount
reported by the Owner's accountants becoming binding on the Contractor. Pending
a final resolution by arbitration, the Owner shall pay the Contractor the amount
certified in the Architect's final Certificate for Payment.

13.5 If, subsequent to final payment and at the Owner's request, the Contractor
incurs costs described in Article 7 and not excluded by Article 8 to correct
defective or nonconforming Work, the Owner shall reimburse the Contractor such
costs and the Contractor's Fee applicable thereto on the same basis as if such
costs had been incurred prior to final payment, but not in excess of the
Guaranteed Maximum Price, if any. If the Contractor has participated in savings
as provided in Paragraph 5.2, the amount of such savings shall be recalculated
and appropriate credit given to the Owner in determining the net amount to be
paid by the Owner to the Contractor.

                                   ARTICLE 14
                            MISCELLANEOUS PROVISIONS

14.1 Where reference is made in this Agreement to a provision of the General
Conditions or another Contract Document, the reference refers to that provision
as amended or supplemented by other provisions of the Contract Documents.

14.2 Payments due and unpaid under the Contract shall bear interest from the
date payment is due at the rate stated below, or in the absence thereof, at the
legal rate prevailing from time to time at the place where the Project is
located.

(Insert rate of interest agreed upon, if any.)

<PAGE>

(Usury laws and requirements under the Federal Truth in Lending Act, similar
state and local consumer credit laws and other regulations at the Owner's and
Contractor's principal places of business, the location of the project and
elsewhere may affect the validity of this provision. Legal advice should be
obtained with respect to deletions or modifications, and also regarding
requirements such as written disclosures or waivers.)

14.3 Other provisions:

1) NDC Development Associates, Repligen Corporation, and West Seyon, LLC are to
be named as additional insureds on Certificates of Insurance.

2) Payment and Performance Bonds are not required.

3) Partial Lien Waivers are to he provided by Contractor and Subcontractors
monthly.

4) Final Lien Releases to be provided upon completion.

                                   ARTICLE 15
                            TERMINATION OR SUSPENSION

15.1 The Contract may be terminated by the Contractor as provided in Article 14
of the General Conditions; however, the amount to be paid to the Contractor
under Subparagraph 14.1.2 of the General Conditions shall not exceed the amount
the Contractor would be entitled to receive under Paragraph 15.3 below, except
that the Contractor's Fee shall be calculated as if the Work had been fully
completed by the Contractor, including a reasonable estimate of the Cost of the
Work for Work not actually completed

15.2 If a Guaranteed Maximum Price is established in Article 5, the Contract may
be terminated by the Owner for cause as provided in Article 14 of the General
Conditions; however, the amount, if any, to be paid to the Contractor under
Subparagraph 14.2.4 of the General Conditions shall not cause the Guaranteed
Maximum Price to be exceeded, nor shall it exceed the amount the Contractor
would be entitled to receive under Paragraph 15.3 below.

15.3 If no Guaranteed Maximum Price is established in Article 5, the Contract
may be terminated by the Owner for cause as provided in Article 14 of the
General Conditions; however, the Owner shall then pay the Contractor an amount
calculated as follows:

15.3 1 Take the Cost of the Work incurred by the Contractor to the date of
termination.

15.3.2 Add the Contractor's Fee computed upon the Cost of the Work to the date
of termination at the rate stated in Paragraph 5.1 or, if the Contractor's Fee
is stated as a fixed sum in that Paragraph, an amount which bears the same ratio
to that fixed-sum Fee as the Cost of the Work at the time of termination bears
to a reasonable estimate of the probable Cost of the Work upon its completion.

15.3.3 Subtract the aggregate of previous payments made by the Owner.

<PAGE>

The Owner shall also pay the Contractor fair compensation, either by purchase or
rental at the election of the Owner, for any equipment owned by the Contractor
which the Owner elects to retain and which is not otherwise included in the Cost
of the Work under Subparagraph 15.3. 1. To the extent that the Owner elects to
take legal assignment of subcontracts and purchase orders (including rental
agreements), the Contractor shall, as a condition of receiving the payments
referred to in this Article 15, execute and deliver all such papers and take all
such steps, including the legal assignment of such subcontracts and other
contractual rights of the Contractor, as the Owner may require for the purpose
of fully vesting in the Owner the rights and benefits of the Contractor under
such subcontracts or purchase orders.

15.4 The Work may be suspended by the Owner as provided in article 14 of the
General Conditions; in such case, the Guaranteed Maximum Price, if any, shall be
increased as provided in Subparagraph 14.3.2 of the General Conditions except
that the term "cost of performance of the Contract" in that Subparagraph shall
be understood to mean the Cost of the Work and the term "profit" shall be
understood to mean the Contractor's Fee as described in Paragraphs 5.1 and 6.3
of this Agreement.

                                   ARTICLE 16
                        ENUMERATION OF CONTRACT DOCUMEMTS

16 1 The Contract Documents, except for Modifications issued after execution of
this Agreement, are enumerated as follows:

16.1.1 The Agreement is this executed Standard Form of Agreement Between Owner
and Contractor, AIA Document Al l 1, 1987 Edition

16.1.2 The General Conditions are the General Conditions of the Contract for
Construction, AIA Document A201, 1987 Edition.

16.1.3 The Supplementary and other Conditions of the Contract are those
contained in the Project Manual dated

                                , and are as follows:

 Document                       Title                                      Pages

 None

16.1.4 The Specifications are those continued in the Project Manual dated as in
Paragraph 16.1.3, and are as follows:

(Either list CPS Specifications here or refer to an exhibit attached to this
Agreement.)

Section                         Title                                      Pages

<PAGE>

None

16.1.5 The Drawings are as follows, and are dated            unless a different
date is shown below:

(Either list the Drawings here or refer to an exhibit attached to this
Agreement.)

Number                          Title                                       Date

See attached 2/13/02 Drawing List - Exhibit 'B'

16.1.6 The Addenda, if any, are as follows:

Number                          Date                                      Pages

Portions of Addenda relating to bidding requirements are not part of the
Contract Documents unless the bidding requirements are also enumerated in this
Article 16.

16.1.7 Other Documents, if any, forming part of the Contract Documents are as
follows: List here any additional documents which are intended to form part of
the Contract Documents. The General Conditions provide that bidding requirements
such as advertisement or invitation to bid, Instructions to Bidders, sample
forms and the Contractor's bid are not part of the Contract Documents unless
enumerated in this Agreements. They should be listed here only if intended to be
part of the Contract Documents.)

Equipment Matrix dated February 7, 2002
Exhibit D - Add/Alternate List

This Agreement is entered into as of the day and year first written above and is
executed in at least three original copies of which one is to be delivered to
the Contractor, one to the Architect for use in the administration of the
Contract, and the remainder to the Owner. OWNER RepliGen Corporation CONTRACTOR
Siena Construction Corporation

/S/ Walter Herlihy                                /s/ Michael S. Barr
 (Signature)                                       (Signature)

Walter Herlihy, President, CEO                    Michael S. Barr, Sr. Proj. Mgr
(Printed name and title                           (Printed name and title)EXHIBIT 10.29

                              ALFACELL CORPORATION
                             PURCHASE AGREEMENT FOR
                             COMMON STOCK & WARRANTS

Alfacell Corporation
225 Belleville Avenue
Bloomfield, New Jersey 07003

Attention: Kuslima Shogen, Chairman
           and Chief Executive Officer

Dear Ms. Shogen:

      The undersigned acknowledges that there is no minimum proceeds requirement
for the closing of this Offering, the Company may close only on the
undersigned's investment and such investment may be inadequate to meet the
Company's cash requirements. The Company intends to utilize the proceeds of this
Offering for research and development and general corporate purposes.

      The undersigned hereby subscribes to purchase _________ units at $_*_ per
unit (the "Unit"). Each Unit consists of one (1) share of Common Stock, $.001
par value per share (the "Shares") of Alfacell Corporation, a Delaware
corporation (the "Company") and one (1) five-year warrant (the "Warrants"). The
Warrants are exercisable into one (1) Share (the "Warrant Shares"). The Shares,
the Warrants and the Warrant Shares are being sold in a transaction exempt from
registration under the Securities Act of 1933, as amended (the "Act"). The
Warrants will be issued pursuant to a Warrant Agreement in the form attached
hereto as Exhibit A executed by the Company for the benefit of the undersigned.
The Warrants will be exercisable at $_**_ for a five-year period commencing
three months after its issuance. The undersigned tenders herewith $_____________
in full payment of the purchase price for the ___________ Units to which the
undersigned subscribes (in the manner indicated on the signature page hereof.).

      The undersigned understands that the right to transfer all or any part of
the Shares, the Warrants and the Warrant Shares (hereinafter sometimes
collectively referred to as the "Securities") will be restricted. The
undersigned may not transfer the Securities unless they are registered under the
Act and applicable state securities or "blue sky" laws, or an exemption from
such registration is available. The undersigned recognizes that the Company
shall have the obligation to register the Securities within ninety days.

      The undersigned hereby represents, warrants and covenants that:

      1.    The undersigned is acquiring the Shares and the Warrants, and at
            such time as the undersigned may exercise the Warrants, the Warrant
            Shares, for the undersigned's own account for investment and not
            with a view towards distribution. The undersigned will not sell,
            hypothecate, transfer or otherwise dispose of the Securities unless
            such transaction has been registered under the Act or, in the
            opinion of counsel for the Company, an exemption from registration
            is available.

      *     The price per unit ranges from $0.40 to $0.50.

      **    The exercise price per share ranges from $0.75 to $1.00.

                                  Page 1 of 11
<PAGE>

      2. (i) Please check here if the representation contained in this paragraph
2(i) is applicable to the undersigned _________. (A) If an individual, (a) the
undersigned's individual net worth or joint net worth with the undersigned's
spouse exceeds $1,000,000 as of the date hereof, or (b) the undersigned's
individual income has been in excess of $200,000 in each of 2000 and 1999 and is
expected to be in excess of $200,000 in 2001, or (c) the undersigned's joint
income with the undersigned's spouse has been in excess of $300,000 in each of
2000 and 1999 and is expected to be in excess of $300,000 in 2001; or (B) if a
corporation, partnership, or other entity, the foregoing representation applies
to all of the equity owners of the corporation, partnership, or entity.

            (ii) If a corporation, partnership, or other entity, was such a
corporation, partnership, or other entity formed for the specific purpose of
acquiring the Shares? _____Yes _____ No

            (iii) If the answer to 2(ii) is yes, how many equity owners does the
corporation partnership or entity have?_______

      3. Whether or not the representation contained in paragraph 2(i) is
applicable to the undersigned, the undersigned has adequate means of providing
for the undersigned's current needs and possible contingencies and has no need
for liquidity of the Securities. The undersigned's overall commitment to
investments is not disproportionate to the undersigned's net worth, and
acquisition of the Securities will not cause such overall commitment to become
excessive. Prior to the execution hereof, the undersigned has received and had
the opportunity to review, examine and read all documents, records and books
pertaining to this investment, including the Company's Annual Report on Form
10-K for the fiscal year ended July 31, 2001, the Company's Quarterly Reports on
Form 10-Q for each of the two quarterly periods subsequent to the fiscal year
ended July 31, 2001 collectively, the "Disclosure Documents").

      4. The undersigned is knowledgeable and experienced in financial and
business matters. The undersigned recognizes and is fully cognizant of the fact
that the investment contemplated hereby involves a high degree of risk. The
undersigned is able to evaluate the merits and risks of an investment in the
Securities. The undersigned has been given an opportunity to ask questions of,
and receive answers and obtain information from, representatives of the Company
concerning the Company.

      5. The undersigned has been given no oral or written representations or
assurances by the Company or any other person acting or purporting to act on
behalf of the Company in connection with the acquisition of the Securities, in
each case except as provided herein or in the Disclosure Documents.

      6. The undersigned understands and specifically acknowledges and agrees
that since the Securities have not been registered under the Act, the
certificates representing the Securities will bear a legend to such effect and a
stop transfer order will be placed on the Securities in the Company's transfer
books.

      7. By its acceptance hereof, the Company hereby agrees that it shall use
its best efforts to file a registration statement (the "Registration Statement")
under the Act to register the resale of the Shares and the Warrant Shares. The
Company further agrees to use its best efforts to cause such Registration
Statement to become effective.

      In connection with the Registration Statement, the undersigned shall
provide the Company, from time to time, as reasonably requested by the Company,
written information concerning its ownership of the Company's Securities, their
intentions concerning the sale of its Shares and Warrant Shares and such other
matters as are required in order to enable the Company to prepare, file and
obtain the effectiveness of such Registration Statement. Notwithstanding any of
the foregoing, the Company shall not be required to maintain the effectiveness
of the Registration Statement for more than two (2) years after the initial
effective date thereof.

                                  Page 2 of 11
<PAGE>

      In connection with any such registration of Shares and Warrant Shares, the
Company shall supply a reasonable number of prospectuses to the undersigned, use
its best efforts to qualify the Shares and Warrants for sale in the states of
New York and New Jersey and furnish indemnification in the manner set forth
below.

      The Company shall bear the entire cost and expense of any such
registration hereunder. Notwithstanding the foregoing, the undersigned shall
bear the fees of all persons retained by it, such as counsel and accountants,
and any transfer taxes or underwriting discounts or commissions applicable to
the Shares and Warrant Shares sold by it pursuant to the Registration Statement.

      The Company shall indemnify and hold harmless each holder of Shares and
Warrant Shares that are registered pursuant to the Registration Statement and
each underwriter, within the meaning of the Act, who may purchase from or sell
for any such holder any such Shares or Warrant Shares and each person, if any,
who controls any such holder or underwriter within the meaning of the Act, from
and against any and all losses, claims, damages and liabilities caused by any
untrue statement of a material fact contained in the Registration Statement or
any post-effective amendment thereto or any prospectus included therein required
to be filed or furnished in connection therewith or caused by any omission to
state therein a material fact required to be stated therein in order to make the
statements made therein, in light of the circumstances under which they were
made, not misleading, except insofar as such losses, claims, damages or
liabilities are caused by any such untrue statement or omission based upon
information furnished or required to be furnished in writing to the Company by
such holder or underwriter expressly for use therein; provided, however, that
such holder or underwriter shall indemnify the Company, its directors, each
officer signing the Registration Statement and each person, if any, who controls
the Company within the meaning of the Act, from and against any and all losses,
claims, damages and liabilities caused by any untrue statement of a material
fact contained in any Registration Statement or any post-effective amendment
thereto or any prospectus included therein required to be filed or furnished
pursuant thereto or caused by any omission to state therein a material fact
required to be stated therein in order to make the statements made therein, in
light of the circumstances under which they were made, not misleading, insofar
as such losses, claims, damages or liabilities are caused by any untrue
statement or omission based upon information furnished in writing to the Company
by any such holder or underwriter expressly for use therein.

      If the indemnification provided for herein from either the holder of the
Shares and Warrant Shares or the Company is unavailable to an indemnified party
(the "Indemnitee") hereunder in respect of any losses, claims, damages or
liabilities (or actions in respect thereof) referred to herein, then the party
responsible for such indemnification (the "Indemnitor"), in lieu of indemnifying
the Indemnitee, shall contribute to the amount paid or payable by the Indemnitee
as a result of such losses, claims, damages or liabilities in such proportion as
is appropriate to reflect the relative fault of the Indemnitor and Indemnitee in
connection with the actions which resulted in such losses, claims, damages or
liabilities (including legal or other fees and expenses reasonably incurred in
connection with any investigation or proceeding) as well as any other equitable
considerations.

      If indemnification is available, the Indemnitor shall indemnify each
Indemnitee to the full extent provided for herein without regard to the relative
fault of the Indemnitor, the Indemnitee or any other equitable consideration
provided for hereunder.

      After the Registration Statement becomes effective and in connection with
the sale of the Shares and Warrant Shares under such Registration Statement, the
undersigned shall take such steps as may be necessary to ensure that the offer
and sale thereof are in compliance with the requirements of the federal
securities laws, including, but not limited to, compliance with the
anti-manipulation requirements of the Securities Exchange Act of 1934, as
amended.

                                  Page 3 of 11
<PAGE>

      By its acceptance hereof, the Company hereby acknowledges that the
foregoing accurately reflects its understanding concerning the transaction
contemplated hereby.

                                        Very truly yours,

                                        ---------------------------------------
                                        (Signature)

                                        ---------------------------------------
                                        Please type or print name
                                        (and title if applicable)

                                        Name & Address (as it should appear on
                                        certificates):

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

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

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

                                        ---------------------------------------
                                        Social Security Number or
                                        Taxpayer Identification Number

                                        (H)__________________  (W)_____________
                                        Telephone Number

                                        ---------------------------------------
                                                     As of Date

                                        ---------------------------------------
                                                   Number of Units

                                        ---------------------------------------
                                               Amount of Subscription
                                                    (U.S. Dollars)

ACCEPTED AND AGREED:                           Deliver to Address: (if
ALFACELL CORPORATION                            different from above)
                                        ---------------------------------------

--------------------------------        ---------------------------------------
Name:  Kuslima Shogen
Title: Chairman and CEO

                                  Page 4 of 11
<PAGE>

                                    Exhibit A

WARRANT TO PURCHASE ___________ SHARES OF COMMON STOCK VOID AFTER 5:00 p.m. NEW
JERSEY TIME, ON ________________. THIS WARRANT AND THE SHARES OF COMMON STOCK
ISSUABLE UPON THE EXERCISE HEREOF HAVE BEEN AND WILL BE ISSUED IN TRANSACTIONS
WHICH HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE
"ACT"), OR UNDER ANY STATE SECURITIES OR BLUE SKY LAWS. THIS WARRANT AND SUCH
SHARES MAY NOT BE SOLD, TRANSFERRED, PLEDGED, HYPOTHECATED OR OTHERWISE DISPOSED
OF, IN WHOLE OR IN PART, IN THE ABSENCE OF AN EFFECTIVE REGISTRATION STATEMENT
UNDER THE ACT AND APPLICABLE STATE LAW, OR AN OPINION OF COUNSEL ACCEPTABLE TO
THE COMPANY THAT SUCH REGISTRATION IS NOT REQUIRED.

NO. _____                                                     ___________ SHARES

                              ALFACELL CORPORATION

      This certifies that, for value received, ___________________________, the
registered holder hereof or assigns (the "Warrantholder") is entitled to
purchase from Alfacell Corporation, a Delaware corporation (the "Company"), at
any time on and after ___________________, and before 5:00 p.m., New Jersey
time, on _______________ (the "Termination Date"), at the purchase price of $___
per share (the "Exercise Price"), the number of shares of Common Stock, par
value $.001 per share, of the Company set forth above (the "Warrant Stock"). The
number of shares of Warrant Stock, the Termination Date and the Exercise Price
per share of this Warrant shall be subject to adjustment from time to time as
set forth below.

SECTION I. TRANSFER OR EXCHANGE OF WARRANT.

      The Company shall be entitled to treat the Warrantholder as the owner in
fact hereof for all purposes and shall not be bound to recognize any equitable
or other claim to or interest in this Warrant on the part of any other person.
This Warrant shall be transferable only on the books of the Company, maintained
at its principal office upon delivery of this Warrant Certificate duly endorsed
by the Warrantholder or by his duly authorized attorney or representative, or
accompanied by proper evidence of succession, assignment or authority to
transfer. Upon any registration of transfer, the Company shall deliver a new
Warrant Certificate or Certificates to the persons entitled thereto.

SECTION II. TERM OF WARRANT; EXERCISE OF WARRANTS.

      A. Termination. The Company may, in its sole discretion, extend the
Termination Date with respect to the exercise of this Warrant upon notice to the
Warrantholder. As used herein, "Termination Date" shall be deemed to include any
such extensions.

      B. Exercise. This Warrant shall be exercised by surrender to the Company,
at its principal office, of this Warrant Certificate, together with the Purchase
Form attached hereto duly completed and signed, and upon payment to the Company
of the Exercise Price for the number of shares of Warrant Stock in respect of
which this Warrant is then exercised. Payment of the aggregate Exercise Price
shall be made in cash or by certified or official bank check.

      C. Warrant Certificate. Subject to Section III hereof, upon such surrender
of this Warrant Certificate and payment of the Exercise Price as aforesaid, the
Company shall issue and cause to be delivered to or upon the written order of
the Warrantholder a certificate or certificates for the number of full shares of
Warrant Stock so purchased upon the exercise of such Warrant, together with
cash, as provided in Section VI hereof, in respect of any fractional shares of
Warrant Stock otherwise issuable

                                  Page 5 of 11
<PAGE>

upon such surrender. Such certificate or certificates representing the Warrant
Stock shall be deemed to have been issued and any person so designated to be
named therein shall be deemed to have become a holder of record of such shares
of Warrant Stock as of the date of receipt by the Company of this Warrant
Certificate and payment of the Exercise Price as aforesaid; provided, however,
that if, at the date of surrender of this Warrant Certificate and payment of the
Exercise Price, the transfer books for the Warrant Stock or other class of stock
purchasable upon the exercise of this Warrant shall be closed, the certificate
or certificates for the shares of Warrant Stock in respect of which this Warrant
is then exercised shall be deemed issuable as of the date on which such books
shall next be opened (whether before or after the Termination Date) and until
such date the Company shall be under no duty to deliver any certificate for such
shares of Warrant Stock; provided further, however, that the transfer books of
record, unless otherwise required by law, shall not be closed at any one time
for a period longer than twenty (20) days. The rights of purchase represented by
this Warrant shall be exercisable, at the election of the Warrantholder, either
in full or from time to time in part, and, in the event that this Warrant is
exercised in respect of fewer than all of the shares of Warrant Stock
purchasable on such exercise at any time prior to the Termination Date, a new
Warrant Certificate evidencing the remaining Warrant or Warrants will be issued,
and the Company shall deliver the new Warrant Certificate or Certificates
pursuant to the provisions of this Section.

SECTION III. PAYMENT OF TAXES.

      The Company will pay all documentary stamp taxes, if any, attributable to
the initial issuance of the shares of Warrant Stock upon the exercise of this
Warrant; provided, however, that the Warrantholder shall pay any tax or taxes
which may be payable in respect of any transfer involved in the issue or
delivery of Warrant Certificates or the certificates for the shares of Warrant
Stock in a name other than that of the Warrantholder in respect of which this
Warrant or shares of Warrant Stock are issued.

SECTION IV. MUTILATED OR MISSING WARRANT CERTIFICATES.

      In case this Warrant Certificate shall be mutilated, lost, stolen or
destroyed, the Company shall, at the request of the Warrantholder, issue and
deliver, in exchange and substitution for and upon cancellation of this
certificate if mutilated, or in lieu of and in substitution for this certificate
if lost, stolen or destroyed, a new Warrant Certificate of like tenor and
representing an equivalent right or interest, but only upon receipt of evidence
satisfactory to the Company of such loss, theft or destruction of this Warrant
Certificate and indemnity, if requested, also satisfactory to the Company.

SECTION V. RESERVATION OF SHARES OF WARRANT STOCK.

      There has been reserved, and the Company shall at all times keep reserved
so long as this Warrant remains outstanding, out of its authorized Common Stock
a number of shares of Common Stock sufficient to provide for the exercise of the
rights of purchase represented by this Warrant. The transfer agent for the
Common Stock and every subsequent transfer agent for any shares of the Company's
capital stock issuable upon the exercise of this Warrant will be irrevocably
authorized and directed at all times to reserve such number of authorized shares
as shall be requisite for such purpose.

SECTION VI. FRACTIONAL SHARES.

      No fractional shares or scrip representing fractional shares shall be
issued upon the exercise of this Warrant. With respect to any fraction of a
share called for upon the exercise of this Warrant, the Company shall pay to the
Warrantholder an amount in cash equal to such fraction multiplied by the current
market price of such fractional share. "Market Price", as of any date means, (i)
the last reported sale price for the shares of Common Stock as reported by the
National Association of Securities Dealers Automated Quotation National Market
System, ("NASDAQ-NMS"), (ii) the closing bid price for the shares of Common
Stock as reported by the National Association of Securities Dealers Automated

                                  Page 6 of 11
<PAGE>

Quotation System ("NASDAQ") if the shares are not traded on NASDAQ-NMS, (iii)
the average of the closing bid and closing asked prices of the Common Stock as
reported by the National Quotations Bureau if the shares are not traded on
NASDAQ; (iv) the last reported sale price, if the shares of Common Stock are
listed on a national securities exchange or (v) if market value cannot be
calculated as of such date on any of the foregoing basis, the fair market price
determined by the Board of Directors of the Company, acting with reasonable
business judgment.

SECTION VII. EXERCISE PRICE; ANTI-DILUTION PROVISIONS.

      A. Exercise Price. The shares of Warrant Stock shall be purchasable upon
the exercise of this Warrant, at a price of $___ per share. The Company may, in
its sole discretion, reduce the Exercise Price applicable to the exercise of
this Warrant upon notice to the Warrantholder. As used herein, "Exercise Price"
shall be deemed to include any such reduction.

      If the Company shall at any time issue Common Stock by way of dividend or
other distribution on any stock of the Company or effect a stock split or
reverse stock split of the outstanding shares of Common Stock, the Exercise
Price shall be proportionately decreased in the case of such issuance (on the
day following the date fixed for determining stockholders entitled to receive
such dividend or other distribution or such stock split) or increased in the
case of such reverse stock split (on the date that such reverse stock split
shall become effective), by multiplying the Exercise Price in effect immediately
prior to the stock dividend or other distribution, stock split or reverse stock
split by a fraction, the numerator of which is the number of shares of Common
Stock outstanding immediately prior to such stock dividend or other
distribution, stock split or reverse stock split, and the denominator of which
is the number of shares of Common Stock outstanding immediately after such stock
dividend or other distribution, stock split or reverse stock split.

      B. No Impairment. The Company (a) will not increase the par value of any
shares of stock receivable upon the exercise of this Warrant above the amount
payable therefor upon such exercise, and (b) will take all such action as may be
necessary or appropriate in order that the Company may validly and legally issue
fully paid and nonassessable shares of Common Stock upon the exercise of this
Warrant.

      C. Number of Shares Adjusted. Upon any adjustment of the Exercise Price
pursuant to this Warrant, the Warrantholder shall thereafter (until another such
adjustment) be entitled to purchase upon the exercise of this Warrant, at the
new Exercise Price, the number of shares, calculated to the nearest full share,
obtained by multiplying the number of shares of Warrant Stock initially issuable
upon exercise of this Warrant by the Exercise Price in effect on the date hereof
and dividing the product so obtained by the new Exercise Price.

SECTION VIII. RECLASSIFICATION, REORGANIZATION OR MERGER.

      In case of any reclassification, capital reorganization or other change of
outstanding shares of Common Stock of the Company (other than a change in par
value or as a result of an issuance of Common Stock by way of dividend or other
distribution or of a stock split or reverse stock split) or in case of any
consolidation or merger of the Company with or into another corporation (other
than a merger with a subsidiary in which merger the Company is the continuing
corporation and which does not result in any reclassification, capital
reorganization or other change of outstanding shares of Common Stock of the
Company issuable upon exercise of this Warrant) or in case of any sale or
conveyance to another corporation of the property of the Company as an entirety
or substantially as an entirety, the Company shall cause effective provision to
be made so that the Warrantholder shall have the right thereafter, by exercising
this Warrant, to purchase the kind and amount of shares of stock and other
securities and property the Warrantholder would have been entitled to receive if
the Warrantholder had exercised this Warrant immediately prior to such
reclassification, capital reorganization or other change, consolidation, merger,
sale or conveyance. Any such provision shall include provision for adjustments
which shall be as

                                  Page 7 of 11
<PAGE>

nearly equivalent as may be practicable to the adjustments provided for in this
Warrant. The foregoing provisions of this Section shall similarly apply to
successive reclassifications, capital reorganizations and changes of shares of
Common Stock and to successive consolidations, mergers, sales and conveyances.

SECTION IX. REGISTRATION RIGHTS.

      A. The Warrantholder shall have the registration rights with respect to
the resale of the Warrant Stock as set forth in Section 7 of the Purchase
Agreement by and between the Company and the Warrantholder of even date
herewith.

SECTION X. NOTICES TO WARRANTHOLDERS.

      So long as this Warrant shall be outstanding and unexercised (a) if the
Company shall pay any dividend or make any distribution upon the Common Stock or
(b) if the Company shall offer to the holders of Common Stock for subscription
or purchase by them any shares of stock of any class or any other rights or (c)
if any capital reorganization of the Company, reclassification of the capital
stock of the Company, consolidation or merger of the Company with or into
another corporation, sale, lease or transfer of all or substantially all of the
assets of the Company to another corporation, or the voluntary or involuntary
dissolution, liquidation or winding up of the Company shall be effected, then,
in any such case, the Company shall cause to be delivered to the Warrantholder,
at least ten days prior to the date specified in (i) or (ii) below, as the case
may be, a notice containing a brief description of the proposed action and
stating the date on which (i) a record is to be taken for the purpose of such
dividend or distribution, or (ii) such reclassification, reorganization,
consolidation, merger, conveyance, lease, dissolution, liquidation or winding up
is to take place and the date, if any, as of which the holders of Common Stock
of record shall be entitled to exchange their shares of Common Stock for
securities or other property deliverable upon such reclassification,
reorganization, consolidation, merger, conveyance, dissolution, liquidation or
winding up.

SECTION XI. NOTICES.

      Any notice pursuant to this Warrant by the Company or by the Warrantholder
shall be in writing and shall be deemed to have been duly given if delivered or
mailed certified mail, return receipt requested, (a) if to the Company, to it at
225 Belleville Avenue, Bloomfield, New Jersey 07003, Attention: Chief Executive
Officer and (b) if to the Warrantholder to the Warrantholder at the address set
forth on the signature page hereto. Each party hereto may from time to time
change the address to which such party's notices are to be delivered or mailed
hereunder by notice in accordance herewith to the other party.

SECTION XII. SUCCESSORS.

      All the covenants and provisions of this Warrant by or for the benefit of
the Company or the Warrantholder shall bind and inure to the benefit of their
respective successors and assigns hereunder.

SECTION XIII. APPLICABLE LAW.

      This Warrant shall be deemed to be a contract made under the laws of the
State of Delaware applicable to agreements made and to be performed entirely in
Delaware and for all purposes shall be construed in accordance with the internal
laws of Delaware without giving effect to the conflicts of laws principles
thereof.

SECTION XIV. BENEFITS OF THIS WARRANT.

                                  Page 8 of 11
<PAGE>

         Nothing in this Warrant shall be construed to give to any person or
corporation other than the Company and the Warrantholder any legal or equitable
right, remedy or claim under this Warrant and this Warrant shall be for the sole
and exclusive benefit of the Company and the Warrantholder.

         IN WITNESS WHEREOF, the parties hereto have executed this Warrant
Certificate or caused this Warrant Certificate to be duly executed as of the day
and year first above written.

ALFACELL CORPORATION

By: ____________________________________
Name:  Kuslima Shogen
Title: Chairman and Chief Executive Officer

WARRANTHOLDER

----------------------------------------
Name:
Address:

----------------------------------------
Social Security or
Taxpayer Identification Number

                                  Page 9 of 11
<PAGE>

                                  PURCHASE FORM

      The undersigned hereby irrevocably elects to exercise the Warrant
represented by this Warrant Certificate to the extent of _____ shares of Common
Stock, par value $.001 per share, of Alfacell Corporation, and hereby makes
payment of $_______ in payment of the actual exercise price thereof.

Name: __________________________________________________________________________
                        (Please type or print in block letters)

Address:________________________________________________________________________
                        (Address for delivery of Stock Certificate)

Social Security or
Taxpayer Identification Number:________________________________________________

Signature:_____________________________________________________________________

                                 Page 10 of 11
<PAGE>

                                 ASSIGNMENT FORM

FOR VALUE RECEIVED, _____________________________ hereby sells, assigns and
transfers unto__________________________________________________________________
(Please type or print in block letters)

Address_________________________________________________________________________
the right to purchase Common Stock, par value $.001 per share, of Alfacell
Corporation, represented by this Warrant Certificate to the extent of __________
shares as to which such right is exercisable and does hereby irrevocably
constitute and appoint ______________________, to transfer the same on the books
of the Company with full power of substitution in the premises.

---------------------------------------
               Signature

Dated:
      ----------------------------------
                                                Notice: The signature of this
                                                assignment must correspond with
                                                the name as it appears upon the
                                                face of this Warrant Certificate
                                                in every particular, without
                                                alteration or enlargement or any
                                                change whatever.

SIGNATURE GUARANTEED:

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

                                 Page 11 of 11

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00039-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00039-of-00352.parquet"}]]