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EXHIBIT 4.3
LETTER AGREEMENT
____________, 1996
▇▇▇▇▇ and Company
▇▇▇▇▇▇▇▇▇▇ Securities
As Representatives of the Several
Underwriters
c/o Cowen and Company
▇▇▇▇▇▇▇▇▇ ▇▇▇▇▇▇, ▇▇▇▇ ▇▇▇▇▇
▇▇▇ ▇▇▇▇, ▇▇ ▇▇▇▇▇
Ladies and Gentlemen:
The undersigned, at the date hereof, is the owner of (or has the right to direct
the disposition of) ____________ shares (including shares issuable upon the
exercise of options or warrants, whether or not presently exercisable) (the
"Shares") of common stock, par value $.01 per share (the "Common Stock"), of
ChemGenics Pharmaceuticals Inc. (the "Company"). The undersigned understands
that the Company has filed a registration statement on Form S-1 (the
"Registration Statement") under the Securities Act of 1933, as amended (the
"Act"), for registration of the sale of _________ shares of Common Stock
(including shares subject to an over-allotment option). The undersigned further
understands that you are contemplating entering into an underwriting agreement
(the "Underwriting Agreement") with the Company in connection with the public
offering of such shares of Common Stock (the "Offering").
In order to induce the Company and you to enter into the Underwriting Agreement
and to proceed with the Offering, the undersigned agrees for the benefit of the
Company and you that the undersigned will not, without the prior written consent
of ▇▇▇▇▇ and Company, directly or indirectly, offer, sell, assign, transfer,
encumber, contract to sell, grant an option to purchase or otherwise dispose of
any shares of Common Stock or securities convertible into or exercisable or
exchangeable for Common Stock (including, without limitation, Common Stock of
the Company which may be deemed to be beneficially owned by the undersigned in
accordance with the rules and regulations under the Act) during the 180 days
following the date on which the price of Common Stock to be purchased by the
Underwriters is set.
Further, the undersigned agrees that prior to the effective date of the
Registration Statement, the undersigned will not, without the prior written
consent of ▇▇▇▇▇ and Company, offer, sell or grant any option for the sale or
otherwise dispose of any shares of Common Stock or any securities convertible
into or exercisable for any shares of Common Stock, owned by the
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undersigned, either directly or indirectly, without first requiring any such
offering or acquiring parties to execute and deliver to you an agreement of
substantially the tenor thereof.
Notwithstanding the foregoing, the undersigned may transfer any or all of the
Shares either during his or her lifetime or on death by gift, will or intestate
succession to his or her immediate family or to a trust the beneficiaries of
which are exclusively the undersigned and/or a member or members of his or her
immediate family; provided, however, that in any such case it shall be a
condition to the transfer that the transferee execute an agreement stating that
the transferee is receiving and holding the Shares subject to the provisions of
this letter agreement, and there shall be no further transfer of such Shares
except in accordance with the letter agreement.
For purposes of this letter agreement, "immediate family" shall mean spouse and
lineal descendent, father, mother, brother or sister of the transferor or his
spouse.
It is understood that, if the Underwriting Agreement does not become effective,
or if the Underwriting Agreement (other than the provisions thereof which
survive termination) shall terminate or be terminated prior to payment for and
delivery of the Shares, you will release the undersigned from any obligations
under the letter agreement.
Sincerely,
_______________________________
_______________________________ ___________________________
Print Name Date
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