HEALTHCARE VENTURES II LP, SC 13D, 1997-02-14

HEALTHCARE VENTURES II LP
SC 13D, 1997-02-14

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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934
(Amendment No. 1 )*

Diacrin, Inc.
- -------------------------------------------------------------------------------
(Name of Issuer)

Common Stock, .01 par value
- -------------------------------------------------------------------------------
(Title of Class of Securities)

25243N103
- -------------------------------------------------------------------------------
(CUSIP Number)

Tina Baker, Esq., Bachner, Tally, Polevoy & Misher LLP
380 Madison Avenue, New York, New York 10017 (212) 687-7000
- -------------------------------------------------------------------------------
(Name, Address and Telephone Number of Person Authorized
to Receive Notices and Communications)

2/16/96 and 10/28/96
- -------------------------------------------------------------------------------
(Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report
the acquisition which is the subject of this Schedule 13D, and is filing this
schedule because of Rule 13d-1(b)(3) or (4), check the following box [ ].

Check the following box if a fee is being paid with the statement [ ]. (A fee is
not required only if the reporting person: (1) has a previous statement on file
reporting beneficial ownership of more than five percent of the class of
securities described in Item 1; and (2) has filed no amendment subsequent
thereto reporting beneficial ownership of five percent or less of such class.)
(See Rule 13d-7.)

Note: Six copies of this statement, including all exhibits, should be filed
with the Commission. See Rule 13d-1(a) for other parties to whom copies are
to be sent.

*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter
disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall be deemed to
be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934
("Act") or otherwise subject to the liabilities of that section of the Act but
shall be subject to all other provisions of the Act (however, see the Notes).

(Continued on following page(s))

Page 1 of 20 Pages

The Exhibit Index appears on page 18.

<PAGE>
SCHEDULE 13D

CUSIP No. 25243N103 Page 2 of 20 pages
------------ ----- -----
-------------------------------------------------------------------
1. NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

HealthCare Ventures II, L.P.

-------------------------------------------------------------------
2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [ ]
(b) [ ]
-------------------------------------------------------------------
3. SEC USE ONLY

-------------------------------------------------------------------
4. SOURCE OF FUNDS*
N/A
-------------------------------------------------------------------
5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
PURSUANT TO ITEMS 2(3) OR 2(e)
[ ]
-------------------------------------------------------------------
6. CITIZENSHIP OR PLACE OF ORGANIZATION

Delaware
-------------------------------------------------------------------
7. SOLE VOTING POWER

-----------------------------------------------
NUMBER OF 8. SHARED VOTING POWER
SHARES
BENEFICIALLY 3,196,385
OWNED BY -----------------------------------------------
EACH 9. SOLE DISPOSITIVE POWER
REPORTING
PERSON
WITH -----------------------------------------------
10. SHARED DISPOSITIVE POWER

3,196,385
-------------------------------------------------------------------
11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

3,196,385
-------------------------------------------------------------------
12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
CERTAIN SHARES* [ ]

-------------------------------------------------------------------
13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

24.5%
-------------------------------------------------------------------
14. TYPE OF REPORTING PERSON

PN
-------------------------------------------------------------------
<PAGE>
SCHEDULE 13D

CUSIP No. 25243N103 Page 3 of 20 pages
------------ ----- -----
-------------------------------------------------------------------
1. NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

HealthCare Partners II, L.P.

Delaware
-------------------------------------------------------------------
7. SOLE VOTING POWER

3,196,385
-------------------------------------------------------------------
11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

3,196,385
-------------------------------------------------------------------
12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
CERTAIN SHARES* [ ]

-------------------------------------------------------------------
13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

24.5%
-------------------------------------------------------------------
14. TYPE OF REPORTING PERSON

PN
-------------------------------------------------------------------
<PAGE>
SCHEDULE 13D

CUSIP No. 25243N103 Page 4 of 20 pages
------------ ----- -----
-------------------------------------------------------------------
1. NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

HealthCare Ventures III, L.P.

-------------------------------------------------------------------
2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [X]
(b) [ ]
-------------------------------------------------------------------
3. SEC USE ONLY

Delaware
-------------------------------------------------------------------
7. SOLE VOTING POWER

-----------------------------------------------
NUMBER OF 8. SHARED VOTING POWER
SHARES
BENEFICIALLY 994,078
OWNED BY -----------------------------------------------
EACH 9. SOLE DISPOSITIVE POWER
REPORTING
PERSON
WITH -----------------------------------------------
10. SHARED DISPOSITIVE POWER

994,078
-------------------------------------------------------------------
11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

994,078
-------------------------------------------------------------------
12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
CERTAIN SHARES* [ ]

-------------------------------------------------------------------
13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

8%
-------------------------------------------------------------------
14. TYPE OF REPORTING PERSON

PN
-------------------------------------------------------------------

<PAGE>
SCHEDULE 13D

CUSIP No. 25243N103 Page 5 of 20 pages
------------ ----- -----
-------------------------------------------------------------------
1. NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

HealthCare Partners III, L.P.

Delaware
-------------------------------------------------------------------
7. SOLE VOTING POWER

994,078
-------------------------------------------------------------------
11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

994,078
-------------------------------------------------------------------
12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
CERTAIN SHARES* [ ]

-------------------------------------------------------------------
13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

8%
-------------------------------------------------------------------
14. TYPE OF REPORTING PERSON

PN
-------------------------------------------------------------------

<PAGE>
SCHEDULE 13D

CUSIP No. 25243N103 Page 6 of 20 pages
------------ ----- -----
-------------------------------------------------------------------
1. NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

HealthCare Ventures IV, L.P.

Delaware
-------------------------------------------------------------------
7. SOLE VOTING POWER

-----------------------------------------------
NUMBER OF 8. SHARED VOTING POWER
SHARES
BENEFICIALLY 291,922
OWNED BY -----------------------------------------------
EACH 9. SOLE DISPOSITIVE POWER
REPORTING
PERSON
WITH -----------------------------------------------
10. SHARED DISPOSITIVE POWER

291,922
-------------------------------------------------------------------
11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

291,922
-------------------------------------------------------------------
12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
CERTAIN SHARES* [ ]

-------------------------------------------------------------------
13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

2%
-------------------------------------------------------------------
14. TYPE OF REPORTING PERSON

PN
-------------------------------------------------------------------
<PAGE>
SCHEDULE 13D

CUSIP No. 25243N103 Page 7 of 20 pages
------------ ----- -----
-------------------------------------------------------------------
1. NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

HealthCare Partners IV, L.P.

Delaware
-------------------------------------------------------------------
7. SOLE VOTING POWER

291,922
-------------------------------------------------------------------
11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

291,922
-------------------------------------------------------------------
12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
CERTAIN SHARES* [ ]

-------------------------------------------------------------------
13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

2%
-------------------------------------------------------------------
14. TYPE OF REPORTING PERSON

PN
-------------------------------------------------------------------
<PAGE>
SCHEDULE 13D

CUSIP No. 25243N103 Page 8 of 20 pages
------------ ----- -----
-------------------------------------------------------------------
1. NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

James H. Cavanaugh, Ph.D.

U.S.A.
-------------------------------------------------------------------
7. SOLE VOTING POWER

-----------------------------------------------
NUMBER OF 8. SHARED VOTING POWER
SHARES
BENEFICIALLY 4,482,385
OWNED BY -----------------------------------------------
EACH 9. SOLE DISPOSITIVE POWER
REPORTING
PERSON
WITH -----------------------------------------------
10. SHARED DISPOSITIVE POWER

4,482,385
-------------------------------------------------------------------
11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

4,482,385
-------------------------------------------------------------------
12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
CERTAIN SHARES* [ ]

-------------------------------------------------------------------
13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

34.4%
-------------------------------------------------------------------
14. TYPE OF REPORTING PERSON

IN
-------------------------------------------------------------------

<PAGE>
SCHEDULE 13D

CUSIP No. 25243N103 Page 9 of 20 pages
------------ ----- -----
-------------------------------------------------------------------
1. NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

Harold R. Werner

U.S.A.
-------------------------------------------------------------------
7. SOLE VOTING POWER

4,482,385
-------------------------------------------------------------------
11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

4,482,385
-------------------------------------------------------------------
12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
CERTAIN SHARES* [ ]

-------------------------------------------------------------------
13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

34.4%
-------------------------------------------------------------------
14. TYPE OF REPORTING PERSON

IN
-------------------------------------------------------------------

<PAGE>
SCHEDULE 13D

CUSIP No. 25243N103 Page 10 of 20 pages
------------ ----- -----
-------------------------------------------------------------------
1. NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

John W. Littlechild

U.S.A.
-------------------------------------------------------------------
7. SOLE VOTING POWER

4,482,385
-------------------------------------------------------------------
11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

4,482,385
-------------------------------------------------------------------
12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
CERTAIN SHARES* [ ]

-------------------------------------------------------------------
13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

34.4%
-------------------------------------------------------------------
14. TYPE OF REPORTING PERSON

IN
-------------------------------------------------------------------

<PAGE>
SCHEDULE 13D

CUSIP No. 25243N103 Page 11 of 20 pages
------------ ----- -----
-------------------------------------------------------------------
1. NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

William Crouse

U.S.A.
-------------------------------------------------------------------
7. SOLE VOTING POWER

4,482,385
-------------------------------------------------------------------
11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

4,482,385
-------------------------------------------------------------------
12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
CERTAIN SHARES* [ ]

-------------------------------------------------------------------
13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

34.4%
-------------------------------------------------------------------
14. TYPE OF REPORTING PERSON

IN
-------------------------------------------------------------------

<PAGE>
Page 12 of 20 Pages
-- ---

Item 1. Security and Issuer

(a) Title of Class of Securities

Common Stock, $0.01 par value ("Shares").

(b) Name of Issuer

Diacrin, Inc.

Building 96, 13th Street
Charlestown Navy Yard
Charlestown, Massachusetts 02129

Item 2. Identity and Background

(a) This statement if filed by HealthCare Ventures II, L.P. ("HCV
II"), HealthCare Partners II, L.P. ("HCP II"), HealthCare
Ventures III, L.P. ("HCV III"), HealthCare Partners III, L.P.
("HCP III"), HealthCare Ventures IV, L.P. ("HCV IV"),
HealthCare Partners IV, L.P. ("HCP IV"), Dr. Cavanaugh and
Messrs. Werner, Littlechild and Crouse. See attached Exhibit
A which is a copy of their agreement in writing to file this
statement on behalf of each of them.(1)

(b) The business address for HCV II, HCP II, HCV III, HCP III,
HCV IV, HCP IV, Dr. Cavanaugh and Messrs. Werner and Crouse
is Twin Towers at Metro Park, 379 Thornall Street, Edison,
New Jersey 08837. The business address for Mr. Littlechild is
One Kendall Square, Building 300, Cambridge, Massachusetts
02139.

(c) James H. Cavanaugh, Ph.D. is the Chairman of HealthCare
Investment Corporation ("HIC"), the management company for
HCV II, HCV III and HCV IV. Messrs. Werner, Littlechild and
Crouse are each a Vice Chairman of HIC. All of the foregoing
individuals are general partners of HCP II, HCP III, and HCP
IV. Mr. Littlechild is also a director of the Issuer.

(d) Each of HCV II, HCP II, HCV III, HCP III, HCV IV, HCP IV, Dr.
Cavanaugh and Messrs. Werner, Littlechild and Crouse have
not, during the last five years, been convicted in a criminal
proceeding (excluding traffic violations or similar
misdemeanors).

(e) Each of HCV II, HCP II, HCV III, HCP III, HCV IV, HCP IV,
Dr. Cavanaugh and
- --------
(1) Dr. Cavanaugh and Messrs. Werner, Littlechild and Crouse are
general partners of HCP II, HCP III and HCP IV, which are the
general partners of each of HCV II, HCV III and HCV IV,
respectively, the record holder of Issuer's securities.

<PAGE>

Page 13 of 20 Pages
------ ------

Messrs. Werner, Littlechild and Crouse have not been, during
the last five years, a party to a civil proceeding of a
judicial or administrative body of competent jurisdiction and
as a result of any such proceeding was or is subject to a
judgment, decree or final order enjoining future violations
of, or prohibiting or mandating activities subject to federal
or state securities laws or finding any violations with
respect to such laws.

(f) HCV II, HCP II, HCV III, HCP III, HCV IV and HCP IV are
limited partnerships organized under the laws of the State of
Delaware. Dr. Cavanaugh and Messrs. Werner, Littlechild and
Crouse are United States citizens.

Item 3. Source and Amount of Funds or Other Considerations

HCV II is a limited partnership formed to provide capital to
companies in the healthcare field. An aggregate of $43,084.80 of
cash from the contributed capital of the limited partners of HCV II
was utilized by HCV II to acquire the Common Stock of Issuer upon
exercise of the Warrants.

Item 4. Purpose of Transaction

The securities of Issuer were acquired for investment purposes by
HCV II, HCV III and HCV IV.

Item 5. Interest in Securities of the Issuer

(a) As of December 31, 1996: (i) HCV II and HCP II beneficially
owned 3,196,385 of Issuer's Common Stock; (ii) HCV III and
HCP III beneficially owned 994,078 Shares of Issuer's Common
Stock; (iii) HCV IV and HCP IV beneficially owned 291,922
Shares of Issuer's Common Stock; and (iv) Dr. Cavanaugh and
Messrs. Werner, Littlechild and Crouse beneficially owned
4,482,385 Shares of Issuer's Common Stock.

As of December 31, 1996: (i) the 3,196,385 Shares of Issuer's
Common Stock beneficially owned by HCV II and HCP II
constitute 24.5% of Issuer's Shares, outstanding; (ii) the
994,078 Shares of Issuer's Common Stock beneficially owned by
HCV III and HCP III constitute 8% of Issuer's Shares
outstanding; (iii) the 291,922 Shares of Issuer's Common
Stock beneficially owned by HCV IV and HCP IV constitute 2%
of Issuer's Shares outstanding; and (iv) the 4,482,385 Shares
of Issuer's Common Stock beneficially owned by Dr. Cavanaugh
and Messrs. Werner, Littlechild and Crouse constitute 34.4%
of Issuer's Shares outstanding.

<PAGE>

Page 14 of 20 Pages
------ ------

(b) Number of shares as to which such person has:

(i) sole power to vote or to direct the vote:

Inapplicable.

(ii) shared power to vote or to direct the vote:

HCV II and HCP II share the power to vote or to
direct the vote of those Shares owned by HCV II. HCV
III and HCP III share the power to vote or to direct
the vote of those Shares owned by HCV III. HCV IV and
HCP IV share the power to vote or to direct the vote
of those Shares owned by HCV IV. Dr. Cavanaugh and
Messrs. Werner, Littlechild and Crouse share the
power to vote or to direct the vote of those Shares
owned by HCV II, HCV III and HCV IV.

(iii) sole power to dispose or to direct the disposition
of:

Inapplicable.

(iv) shared power to dispose of or to direct the
disposition of:

HCV II and HCP II share the power to dispose of or to
direct the disposition of those Shares owned by HCV
II. HCV III and HCP III share the power to dispose of
or to direct the disposition of those Shares owned by
HCV III. HCV IV and HCP IV share the power to dispose
of or to direct the disposition of those Shares owned
by HCV IV. Dr. Cavanaugh and Messrs. Werner,
Littlechild and Crouse share the power to dispose of
or to direct the disposition of those Shares owned by
HCV II, HCV III and HCV IV.

(c) As a result of the closing of the Issuer's initial public
offering on February 16, 1996: (i) the 6,380,802 Shares of
Preferred Stock beneficially owned by HCV II and HCP II were
automatically converted into 3,190,401 Shares of Issuer's
Common Stock, giving effect to a one-for-two reverse stock
split of the Issuer's Common Stock (the "Reverse Stock
Split"); (ii) the $2,485,195 principal amount of 7-1/2%
Convertible Notes due May 31, 2000 (the "Notes") beneficially
owned by HCV III and HCP III were automatically converted
into 994,078 Shares of Issuer's Common Stock, giving effect
to the Reverse Stock Split; and (iii) the $729,805 of Notes
beneficially owned by HCV IV and HCP IV were automatically
converted into 291,922 Shares of Issuer's Common Stock,
giving effect to the Reverse Stock Split.

On October 28, 1996, HCV II exercised the 11,968 Common Stock
Warrants beneficially owned by it and was issued 5,984 Shares
of Issuer's Common Stock, giving effect to the Reverse Stock
Split

(d) Inapplicable

(e) Inapplicable
<PAGE>

Page 15 of 20 Pages
------ ------

Item 6. Contracts, Arrangements, Understandings or Relationship with
respect to Securities of the Issuer

On March 26, 1992, HCV III and HCV IV entered into an InterFund
Agreement which provides for HCV III and HCV IV to coordinate their
investment activities so as to acquire, hold and dispose of
identical securities in proportion to their respective contributed
capital.

Item 7. Materials to Be Filed as Exhibits

(A) Agreement to Jointly File

(B) InterFund Agreement dated as of March 26, 1992 between HCV III
and HCV IV.*

*Previously filed as an Exhibit to the Schedule 13D filed by HCV III and HCV IV
on June 9, 1995.
<PAGE>

Page 16 of 20 Pages
------ ------

SIGNATURES

After reasonable inquiry and to the best of my knowledge and
belief, I certify that the information set forth in this statement is true,
complete and correct.
<TABLE>

<S> <C>
Dated: February 13, 1997 HealthCare Ventures II, L.P.,
Edison, New Jersey by its General Partner, HealthCare Partners II, L.P.

By: /s/ Jeffrey Steinberg
-----------------------------
Administrative Partner

Dated: February 13, 1997 HealthCare Partners II, L.P.
Edison, New Jersey

By: /s/ Jeffrey Steinberg
-----------------------------
Administrative Partner

Dated: February 13, 1997 HealthCare Ventures III, L.P.
Edison, New Jersey by its General Partner, HealthCare Partners III, L.P.

By: /s/ Jeffrey Steinberg
-----------------------------
Administrative Partner

Dated: February 13, 1997 HealthCare Partners III, L.P.
Edison, New Jersey

By: /s/ Jeffrey Steinberg
-----------------------------
Administrative Partner

Dated: February 13, 1997 HealthCare Ventures IV, L.P.
Edison, New Jersey by its General Partner, HealthCare Partners IV, L.P.

By: /s/ Jeffrey Steinberg
-----------------------------
Administrative Partner

</TABLE>

<PAGE>

Page 17 of 20 Pages
------ ------

<TABLE>
<S> <C>
Dated: February 13, 1997 HealthCare Partners IV, L.P.
Edison, New Jersey

By: /s/ Jeffrey Steinberg
-----------------------------
Administrative Partner

Dated: February 13, 1997 By: /s/ Jeffrey Steinberg as Attorney-in-Fact
Edison, New Jersey -----------------------------
James H. Cavanaugh, Ph.D.

Dated: February 13, 1997 By: /s/ Jeffrey Steinberg as Attorney-in-Fact
Edison, New Jersey -----------------------------
Harold R. Werner

Dated: February 13, 1997 By: /s/ Jeffrey Steinberg as Attorney-in-Fact
Cambridge, Massachusetts ----------------------------
John W. Littlechild

Dated: February 13, 1997 By: /s/ Jeffrey Steinberg as Attorney-in-Fact
Edison, New Jersey -----------------------------
William Crouse

</TABLE>

<PAGE>
EXHIBIT INDEX

Exhibit Description Page No.
------- ----------- --------

Exhibit A Agreement to Jointly File 19

<PAGE>

Page 19 of 20 Pages
------ ------

EXHIBIT A

AGREEMENT

JOINT FILING OF SCHEDULE 13D

The undersigned hereby agree to jointly prepare and file with
regulatory authorities a Schedule 13D and any future amendments thereto
reporting each of the undersigned's ownership of securities of Diacrin, Inc. and
hereby affirm that such Schedule 13D is being filed on behalf of each of the
undersigned.

Dated: February 13, 1997 HealthCare Ventures II, L.P.,
Edison, New Jersey by its General Partner, HealthCare Partners II, L.P.

By: /s/ Jeffrey Steinberg
--------------------------
Administrative Partner

Dated: February 13, 1997 HealthCare Partners II, L.P.
Edison, New Jersey

By: /s/ Jeffrey Steinberg
----------------------------
Administrative Partner

Dated: February 13, 1997 HealthCare Ventures III, L.P.
Edison, New Jersey by its General Partner, HealthCare Partners III, L.P.

By: /s/ Jeffrey Steinberg
--------------------------
Administrative Partner

Dated: February 13, 1997 HealthCare Partners III, L.P.
Edison, New Jersey

By: /s/ Jeffrey Steinberg
---------------------------
Administrative Partner

</TABLE>

<PAGE>

Page 20 of 20 Pages
----- ----
<TABLE>
<CAPTION>
<S> <C>
Dated: February 13, 1997 HealthCare Ventures IV, L.P.
Edison, New Jersey by its General Partner, HealthCare Partners IV, L.P.

By: /s/ Jeffrey Steinberg
----------------------
Administrative Partner

Dated: February 13, 1997 HealthCare Partners IV, L.P.
Edison, New Jersey

By: /s/ Jeffrey Steinberg
----------------------
Administrative Partner

Dated: February 13, 1997 By: /s/ Jeffrey Steinberg as Attorney-in-Fact
Edison, New Jersey -------------------------
James H. Cavanaugh, Ph.D.

Dated: February 13, 1997 By: /s/ Jeffrey Steinberg as Attorney-in-Fact
Edison, New Jersey ----------------------
Harold R. Werner

Dated: February 13, 1997 By: /s/ Jeffrey Steinberg as Attorney-in-Fact
Cambridge, Massachusetts ----------------------
John W. Littlechild

Dated: February 13, 1997 By: /s/ Jeffrey Steinberg as Attorney-in-Fact
Edison, New Jersey ----------------------
William Crouse

</TABLE>