Exhibit 4
                                FORM OF WARRANT

                                     WARRANT
                       TO PURCHASE SHARES OF COMMON STOCK
                                       OF
                          BIOMARIN PHARMACEUTICAL INC.


     THE WARRANTS REPRESENTED BY THIS CERTIFICATE AND THE SHARES OF COMMON STOCK
ISSUABLE  UPON  EXERCISE  OF THIS  WARRANT  HAVE NOT BEEN  REGISTERED  UNDER THE
SECURITIES ACT OF 1933, AND NEITHER THESE WARRANTS NOR ANY INTEREST  THEREIN MAY
BE TRANSFERRED, HYPOTHECATED OR OTHERWISE DISPOSED OF WITHOUT REGISTRATION UNDER
THAT  ACT  OR AN  OPINION  OF  COUNSEL  ACCEPTABLE  TO  THE  COMPANY  THAT  SUCH
REGISTRATION IS NOT REQUIRED.

No. _______                                  Warrant to Purchase _______ Shares
May 16, 2001                                 of Common Stock, $0.001 Per Share




                        WARRANT TO PURCHASE COMMON STOCK
                                       of
                          BIOMARIN PHARMACEUTICAL INC.,
                             a Delaware corporation
           Void after the date set forth in the first paragraph hereof


     This certifies  that,  for value  received,  ______________,  or registered
assigns  ("Holder")  is  entitled,  subject  to the terms set  forth  below,  to
purchase  from  BioMarin   Pharmaceutical  Inc.,  a  Delaware  corporation  (the
"Company"),  ______  shares of Common  Stock,  $0.001 par value,  of the Company
(such class of stock being referred to herein as "Common Stock"), as constituted
on May 16, 2001 (the "Issue  Date"),  upon  surrender  of this  Warrant,  at the
principal  office of the Company referred to below,  with the subscription  form
attached  hereto  duly  executed,  and  simultaneous  payment  therefor  in  the
consideration  specified  in Section 1 hereof,  at the price of $13.10 per share
(the "Purchase Price"). This Warrant must be exercised,  if at all, prior to the
earlier to occur of (i) the third anniversary of the Issue Date or (ii) the date
of  consummation  of  the  acquisition  of  the  Company   (including,   without
limitation,  any  reorganization,  merger or consolidation)  that results in the
stockholders of the Company  immediately  prior to such consummation date owning
less  than  50% of the  voting  power  of the  surviving  entity  or the date of
consummation  of the  sale  of all or  substantially  all of the  assets  of the
Company or the date of dissolution or liquidation of the Company (each a "Change
of Control  Transaction").  The shares of Common Stock  issued or issuable  upon
exercise of this Warrant are sometimes  referred to as the "Warrant Shares." The
term  "Warrants"  as used herein  shall  include  this  Warrant and any warrants
delivered in substitution or exchange therefor as provided herein.

     9.  Exercise.  This  Warrant may be  exercised  at any time or from time to
time, on any business day, for all or part of the full number of Warrant  Shares
during the period of time described  above,  by surrendering it at the principal
office of the Company,  371 Bel Marin Keys Blvd., Suite 210, Novato,  California
94949,  with the  subscription  form in the form attached  hereto duly executed,
together with payment for the Warrant  Shares to be purchased,  payable in cash,
cashier's  check and/or wire transfer of immediately  available  funds. No other
form of  consideration  shall be acceptable for the exercise of this Warrant.  A
Warrant shall be deemed to have been exercised immediately prior to the close of
business on the date of its  surrender  for exercise  together  with delivery of
payment  therefor  as  provided  above,  and the person  entitled to receive the
shares of Common  Stock  issuable  upon such  exercise  shall be treated for all
purposes as the record holder of such shares as of the close of business on such
date. As soon as  practicable  on or after such date, and in any event within 10
days  thereof,  the  Company  shall  issue and  deliver to the person or persons
entitled to receive the same a  certificate  or  certificates  for the number of
shares of Common Stock issuable upon such exercise.  Upon any partial  exercise,
the Company  will issue and deliver to Holder a new Warrant  with respect to the
Warrant Shares not previously  purchased.  No fractional  shares of Common Stock
shall be issued upon exercise of a Warrant.  In lieu of any fractional  share to
which Holder would be entitled upon  exercise,  the Company shall pay cash equal
to the product of such fraction multiplied by the then current fair market value
of one share of Common Stock, as determined in good faith by the Company.

     10.  Payment of Taxes.  All shares of Common Stock issued upon the exercise
of a Warrant shall be duly  authorized,  validly issued and  outstanding,  fully
paid and  non-assessable.  Holder  shall pay all  taxes  and other  governmental
charges that may be imposed in respect of the issue or delivery  thereof and any
tax or other charge  imposed in  connection  with any  transfer  involved in the
issue of any  certificate for shares of Common Stock in any name other than that
of the  registered  Holder of the Warrant  surrendered  in  connection  with the
purchase of such shares,  and in such case the Company  shall not be required to
issue or deliver any stock  certificate  until such tax or other charge has been
paid or it has been  established  to the Company's  satisfaction  that no tax or
other charge is due.

     11. Transfer and Exchange. Subject to the restrictions set forth in Section
8.1(d), this Warrant and all rights hereunder are transferable, in whole but not
in part, only with the prior approval of the Company, which consent shall not be
unreasonably withheld. If such a proposed transfer is so approved,  this Warrant
is transferable  on the books of the Company  maintained for such purpose at its
principal  office  referred  to above by Holder in person or by duly  authorized
attorney,  upon surrender of this Warrant properly  endorsed and upon payment of
any  necessary  transfer  tax or other  governmental  charge  imposed  upon such
transfer.  Each taker and holder of this Warrant, by taking or holding the same,
consents and agrees that this Warrant,  when endorsed in blank,  shall be deemed
negotiable  and that when this Warrant  shall have been so endorsed,  the Holder
hereof may be treated by the Company  and all other  persons  dealing  with this
Warrant as the absolute owner hereof for any purpose and as the person  entitled
to exercise the rights represented hereby or to the transfer hereof on the books
of the  Company,  any  notice to the  contrary  notwithstanding;  but until such
transfer on such books,  the Company may treat the  registered  Holder hereof as
the owner for all purposes.

12.      Certain Adjustments.


     12.1 Adjustment for Reorganization,  Consolidation,  Merger.  Other than in
any case a Change of Control Transaction, in case of any reclassification of the
Common Stock, or other securities  issuable upon exercise of this Warrant, or in
case  of any  reorganization  of the  Company  (or,  in  each  case,  any  other
corporation,  the stock or other  securities of which are at the time receivable
on the exercise of this Warrant)  after the Issue Date,  or in case,  after such
date,  the Company (or any such other  corporation)  shall  consolidate  with or
merge into  another  corporation,  then and in each such case  Holder,  upon the
exercise  hereof as provided in Section 1 at any time after the  consummation of
such reorganization,  consolidation,  merger or conveyance, shall be entitled to
receive, in lieu of the stock receivable upon the exercise of this Warrant prior
to such  consummation,  the stock or other  securities or property to which such
Holder  would  have been  entitled  upon such  consummation  if such  Holder had
exercised this Warrant immediately prior thereto.

     12.2  Adjustments for Dividends in Common Stock. If the Company at any time
or from time to time after the Issue Date makes,  or fixes a record date for the
determination of holders of Common Stock entitled to receive, a dividend payable
in additional  shares of Common Stock,  then and in each such event the Purchase
Price then in effect shall be  decreased as of the time of such  issuance or, in
the event such record date is fixed,  as of the close of business on such record
date,  by  multiplying  the Purchase  Price then in effect by a fraction (1) the
numerator  of which is the total  number of shares of Common  Stock  issued  and
outstanding  immediately  prior to the  time of such  issuance  or the  close of
business  on such record  date,  and (2) the  denominator  of which shall be the
total number of shares of Common Stock issued and outstanding  immediately prior
to the time of such  issuance  or the close of business on such record date plus
the number of shares of Common  Stock  issuable  in  payment  of such  dividend;
provided,  however,  that if such record date is fixed and such  dividend is not
fully paid on the date fixed  therefore,  the Purchase Price shall be recomputed
accordingly  as of the close of business on such record date and  thereafter the
Purchase Price shall be adjusted  pursuant to this Section 4.2 as of the time of
actual payment of such dividends.

     12.3 Stock Split and  Reverse  Stock  Split.  If the Company at any time or
from time to time after the Issue Date effects a subdivision of the  outstanding
Common  Stock,  the  Purchase  Price  then in  effect  immediately  before  that
subdivision  shall be  proportionately  decreased  and the  number  of shares of
Common Stock  theretofore  receivable upon the exercise of this Warrant shall be
proportionately increased. If the Company at any time or from time to time after
the Issue Date  combines the  outstanding  shares of Common Stock into a smaller
number of shares,  the  Purchase  Price then in effect  immediately  before that
combination  shall be  proportionately  increased  and the  number  of shares of
Common Stock  theretofore  receivable upon the exercise of this Warrant shall be
proportionately  decreased.  Each adjustment under this Section 4.3 shall become
effective at the close of business on the date the  subdivision  or  combination
becomes effective.

     12.4  Accountants'  Certificate  as  to  Adjustment.  In  each  case  of an
adjustment  in the Purchase  Price or shares of Common Stock  receivable  on the
exercise of the  Warrants,  the Company at its expense  shall cause  independent
public  accountants of recognized  standing  selected by the Company (who may be
the independent  public  accountants  then auditing the books of the Company) to
compute such adjustment in accordance with the terms of this Warrant and prepare
a  certificate  setting forth such  adjustment  and showing the facts upon which
such  adjustment is based.  Any such  certificate as prepared by the independent
public accountants shall, upon delivery to the Holder, be conclusive evidence of
the accuracy of such adjustment.

     13.  Loss  or   Mutilation.   Upon  receipt  by  the  Company  of  evidence
satisfactory  to it (in the exercise of reasonable  discretion) of the ownership
of and the loss,  theft,  destruction  or  mutilation of any Warrant and (in the
case of loss,  theft or  destruction)  of indemnity  satisfactory  to it (in the
exercise  of  reasonable  discretion),  and (in the  case  of  mutilation)  upon
surrender and cancellation thereof, the Company will execute and deliver in lieu
thereof a new Warrant of like tenor.

     14. Reservation of Common Stock. The Company shall at all times reserve and
keep available out of its authorized but unissued shares of Common Stock, solely
for the purpose of effecting  the  exercise of the  Warrant,  such number of its
shares  of  Common  Stock as shall  from  time to time be  sufficient  to effect
exercise  of the  Warrant;  and if at any  time the  number  of  authorized  but
unissued shares of Common Stock shall not be sufficient to effect such exercise,
the  Company  will take such  corporate  action as may,  in the  opinion  of its
counsel,  be necessary to increase its authorized but unissued  shares of Common
Stock to such number of shares as shall be sufficient for such purpose.

     15.  Notices of Record Date.  In the event of (i) any taking by the Company
of a record  of the  holders  of any  class of  securities  for the  purpose  of
determining  the  holders  thereof who are  entitled to receive any  dividend or
other  distribution,  or (ii) any capital  reorganization  of the  Company,  any
reclassification or  recapitalization  of the capital stock of the Company,  any
merger or consolidation of the Company with or into any other corporation (other
than a merger of a wholly owned subsidiary into the Company), or any transfer of
all or substantially all of the assets of the Company to any other person or any
voluntary or involuntary dissolution,  liquidation or winding up of the Company,
the Company  shall  provide to the  Holder,  at least ten (10) days prior to the
record date  specified  therein,  a notice  specifying (1) the date on which any
such record is to be taken for the purpose of such dividend or distribution  and
a description of such dividend or  distribution,  (2) the date on which any such
reorganization,  reclassification, transfer, consolidation, merger, dissolution,
liquidation or winding up is expected to become effective,  and (3) the date, if
any,  that is to be fixed,  as to when the holders of record of Common Stock (or
other securities) shall be entitled to exchange their shares of Common Stock (or
other  securities)  for  securities  or other  property  deliverable  upon  such
reorganization,  reclassification, transfer, consolidation, merger, dissolution,
liquidation or winding up.

16.      Investment Representation and Restriction on Transfer.

16.1     Securities Law Requirements.

     (a) By its  acceptance  of  this  Warrant,  Holder  hereby  represents  and
warrants  to the  Company  that this  Warrant  and the  Warrant  Shares  will be
acquired for investment for its own account,  not as a nominee or agent, and not
with a view to the sale or distribution of any part thereof,  and that it has no
present   intention  of  selling,   granting   participations  in  or  otherwise
distributing the same. By acceptance of this Warrant,  Holder further represents
and  warrants  that it does not have any  contract,  undertaking,  agreement  or
arrangement  with any person to sell,  transfer or grant  participations  to any
person, with respect to this Warrant or the Warrant Shares.

     (b) By its acceptance of this Warrant, Holder understands that this Warrant
is not, and the Warrant Shares will not be,  registered under the Securities Act
of 1933, as amended (the "Act"),  on the basis that the issuance of this Warrant
and the Warrant  Shares are exempt from  registration  under the Act pursuant to
Section  4(2)  thereof,  and that the  Company's  reliance on such  exemption is
predicated on Holder's representations and warranties set forth herein.

     (c) By its acceptance of this Warrant,  Holder understands that the Warrant
and the Warrant Shares may not be sold,  transferred,  or otherwise  disposed of
without registration under the Act, or an exemption  therefrom,  and that in the
absence of an  effective  registration  statement  covering  the Warrant and the
Warrant Shares or an available  exemption from  registration  under the Act, the
Warrant and the Warrant Shares must be held indefinitely.  In particular, Holder
is aware that the  Warrant and the  Warrant  Shares may not be sold  pursuant to
Rule 144 promulgated  under the Act unless all of the conditions of Rule 144 are
satisfied.  Among the  conditions  for use of Rule 144 are the  availability  of
current information about the Company to the public,  prescribed holding periods
which will commence only upon Holder's  payment for the  securities  being sold,
manner of sale restrictions,  volume limitations and certain other restrictions.
By its acceptance of this Warrant,  Holder  represents and warrants that, in the
absence of an  effective  registration  statement  covering  the  Warrant or the
Warrant Shares,  it will sell,  transfer or otherwise dispose of the Warrant and
the Warrant  Shares only in a manner  consistent  with its  representations  and
warranties  set forth herein and then only in accordance  with the provisions of
Section 8.1(d).

     (d) By its acceptance of this Warrant,  Holder agrees that in no event will
it transfer or dispose of any of the  Warrants or the Warrant  Shares other than
pursuant to an effective  registration statement under the Act, unless and until
(i) Holder shall have notified the Company of the proposed disposition and shall
have furnished the Company with a statement of the circumstances surrounding the
disposition,  and (ii) if requested by the Company, at the expense of the Holder
or  transferee,  it shall have  furnished  to the Company an opinion of counsel,
reasonably satisfactory to the Company, to the effect that (A) such transfer may
be made without  registration under the Act and (B) such transfer or disposition
will not cause the termination or the  non-applicability of any exemption to the
registration  and  prospectus  delivery  requirements  of  the  Act  or  to  the
qualification  or registration  requirements of the securities laws of any other
jurisdiction  on which the Company  relied in issuing the Warrant or the Warrant
Shares.

16.2      Legends; Stop Transfer.

     (a) All  certificates  evidencing the Warrant Shares shall bear a legend in
substantially the following form:

                  The securities represented by this certificate have not been
                  registered under the Securities Act of 1933. These securities
                  have been acquired for investment and not with a view to
                  distribution and may not be offered for sale, sold, pledged or
                  otherwise transferred in the absence of an effective
                  registration statement for such securities under the
                  Securities Act of 1933 or an opinion of counsel reasonably
                  satisfactory in form and content to the issuer that such
                  registration is not required under such Act.

     (b) The  certificates  evidencing  the Warrant  Shares  shall also bear any
legend required by any applicable state securities law.

     (c) In addition,  the Company  shall make,  or cause its transfer  agent to
make,  a notation  regarding  the transfer  restrictions  of the Warrant and the
Warrant Shares in its stock books,  and the Warrant and the Warrant Shares shall
be  transferred on the books of the Company only if transferred or sold pursuant
to an  effective  registration  statement  under  the Act  covering  the same or
pursuant  to and in  compliance  with the  provisions  of Section 3 and  Section
8.1(d).

     17. Notices.  All notices and other  communications from the Company to the
Holder of this Warrant  shall be mailed by  first-class  registered or certified
mail,  postage  prepaid,  to the address  furnished to the Company by Holder and
shall be deemed received five (5) business days after mailing.

     18.  Change;  Waiver.  Neither  this  Warrant  nor any term  hereof  may be
changed,  waived,  discharged or terminated orally, but only by an instrument in
writing  signed by the party against which  enforcement  of the change,  waiver,
discharge or termination is sought.

     19. Headings.  The headings in this Warrant are for purposes of convenience
in reference only, and shall not be deemed to constitute a part hereof.

                     [Reminder of Page Intentionally Blank]






     20.  Governing  Law. This Warrant is delivered in  California  and shall be
construed and enforced in accordance with and governed by the internal laws, and
not the law of conflicts,  of such State;  provided however,  that to the extent
that an issue of  determination  is one of  corporation  law,  then the Delaware
General Corporation Law shall govern.

                      BIOMARIN PHARMACEUTICAL INC.,
                      a Delaware corporation

                 By:  /s/ Raymond W. Anderson
                     ---------------------------------------------
                     Raymond W. Anderson, Chief Operating Officer







                                SUBSCRIPTION FORM
                 (To be executed only upon exercise of Warrant)

     The undersigned,  registered owner of this Warrant,  irrevocably  exercises
this Warrant and purchases ____________ of the number of shares of Common Stock,
$0.001 par value,  of  BioMarin  Pharmaceutical  Inc.,  a Delaware  corporation,
purchasable with this Warrant,  and herewith makes payment therefor,  all at the
price and on the terms and conditions specified in this Warrant.

DATED:  ______________


                         -------------------------------------------------------
                         (Signature of Registered Owner)

                         -------------------------------------------------------
                         (Street Address)

                         -------------------------------------------------------
                         (City)        (State)    (Zip)





                               FORM OF ASSIGNMENT

     FOR VALUE  RECEIVED  the  undersigned,  registered  owner of this  Warrant,
hereby  sells,  assigns and transfers  unto the Assignee  named below all of the
rights of the undersigned  under the within Warrant,  with respect to the number
of shares of Common Stock, $0.001 par value, set forth below:

Name of Assignee                Address                           No. of Shares





     and     does     hereby     irrevocably      constitute     and     appoint
_________________________      _________________________________________________
Attorney to make such transfer on the books of BioMarin  Pharmaceutical  Inc., a
Delaware   corporation,   maintained  for  the  purpose,   with  full  power  of
substitution in the premises.

DATED:  ___________________

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

                                    --------------------------------------------
                                    (Witness)




                          Schedule of Warrant Holders

- ------------------------------------------------- -----------------------
Warrant Holder                                      Number of Warrants
- ------------------------------------------------- ----------------------

BayStar Capital LP                                       21,164
- ------------------------------------------------- ----------------------
BayStar International Ltd.                               10,582
- ------------------------------------------------- ----------------------
equityfourlife (Bahamas) Ltd.                            95,238
- ------------------------------------------------- ----------------------
Perceptive Life Sciences Fund LP                         15,873
- ------------------------------------------------- ----------------------
MPM BioEquities Master Fund LP                           63,492
- ------------------------------------------------- ----------------------
Pequot Scout Fund L.P.                                   20,635
- ------------------------------------------------- ----------------------
Pequot Navigator Offshore Fund, Inc.                     11,111
- ------------------------------------------------- ----------------------
Caduceus Capital Trust                                   54,750
- ------------------------------------------------- ----------------------
Caduceus Capital II, LP                                  30,750
- ------------------------------------------------- ----------------------
PW Eucalyptus Fund, L.L.C.                               66,750
- ------------------------------------------------- ----------------------
PW Eucalyptus Fund, Ltd                                   6,750
- ------------------------------------------------- ----------------------
Franklin California Growth Fund- Class A (2)            142,857
- ------------------------------------------------- ----------------------
Franklin Biotechnology Discovery Fund (3)                95,238
- ------------------------------------------------- ----------------------
Orbitex Health & Biotechnology Fund (4)                  41,269
- ------------------------------------------------- ----------------------
Orbitex Life Science & Biotechnology Fund (5)             4,762
- ------------------------------------------------- ----------------------
Monument Medical Science Fund (6)                        17,460
- ------------------------------------------------- ----------------------
Ursus Capital L.P.                                       12,476
- ------------------------------------------------- ----------------------
Ursus Offshore Ltd.                                       3,397
- ------------------------------------------------- ----------------------
Biotech Value Plus Ltd.                                  15,873
- ------------------------------------------------- ----------------------
SCO Securities LLC                                       22,000
- ------------------------------------------------- ----------------------