REGISTRATION RIGHTS AGREEMENT


         THIS REGISTRATION  RIGHTS AGREEMENT (the "Agreement") is made by Cheung
Laboratories,  Inc., a Maryland corporation (the "Company"),  for the benefit of
the undersigned  investor  ("Investor",  collectively,  the  "Investors").  This
Agreement  shall become  effective upon acceptance and closing in respect of the
related  subscription  for  the  Senior  Secured  Convertible  Promissory  Notes
("Notes")  and  the  shares  of  common  stock  underlying  the  Notes,  and the
associated  warrants to purchase common stock of the Company  ("Warrants").  The
Notes and the Warrants are collectively  referred to herein as the "Securities."
The common  stock of the Company  into which the Notes are  convertible  and the
common stock  issuable upon exercise of the Warrants shall be referred to herein
collectively as the "Underlying Stock."

                                 R E C I T A L S

         A. The Investors  desire to purchase from the Company,  and the Company
desires to issue and sell to the Investors,  up to an aggregate of $1,505,000 in
face amount of Notes and  associated  Warrants as described in the  Confidential
Offering  Memorandum  dated  January 6, 1997 as amended June 12, 1997 and all of
the Exhibits thereto (the "Offering Memorandum").

         B. As further  inducement  for the  Investors to purchase the Notes and
Warrants from the Company,  the Company hereby  undertakes to register under the
Securities  Act of 1933, as amended,  and the rules and  regulations  thereunder
(collectively,  the "Securities  Act"),  the Underlying  Stock upon the first to
occur of (i) six months after the Company effects a  registration,  or (ii) July
10, 1998, on any applicable form, of newly issued common stock at any time while
the Investor  holds the Notes,  the Warrants,  or some or all of the  Underlying
Stock. This Agreement sets forth the terms and conditions of such undertaking.

         The Company and the Investor agree as follows:

         1.       Definitions.  For purposes of this Agreement:

                  (a) The  terms  "register,"  "registered"  and  "registration"
         refer to a registration effected by preparing and filing a registration
         statement or  statements or similar  documents in  compliance  with the
         Securities Act and pursuant to Rule 415 under the Securities Act or any
         successor rule providing for offering  securities on a continuous basis
         ("Rule 415"),  and the declaration or ordering of effectiveness of such
         registration  statement  or document  by the  Securities  and  Exchange
         Commission (the "SEC").

                  (b)  The  term   "Registerable   Securities"   means  (i)  the
         Underlying  Stock,  and (ii) any common stock of the Company  issued as
         (or  issuable  upon  the  conversion  or  exercise  of any  convertible
         security,  warrant,  right or other  security  which  is  issued  as) a
         dividend or other  distribution  with respect to, or in exchange for or
         in replacement of any Note, Warrant, or any Underlying Stock, excluding
         in all cases, however, any Registerable  Securities sold by a holder of
         such Registerable Securities in a transaction in which its registration
         rights under this Agreement are not assigned.

                  (c) The  Investors  and  assignees  with  registration  rights
         assigned  to  them  pursuant  to  Section  8 of this  Agreement  may be
         referred to herein collectively as "Holders" of Registerable Securities
         and each may be  referred  to  herein  as a  "Holder"  of  Registerable
         Securities.

         2.       Registration.

                  (a)  Automatic   Registration  Right  -  (i)  Subject  to  the

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         provisions of Section 3(a),  below and no earlier than six months after
         the final closing date (the "Closing Date") of a registered offering of
         the common  stock of the  Company to the  general  public  covered by a
         registration  statement  under the Securities Act ("Public  Offering"),
         the  Company  shall use good faith  efforts to effect the  registration
         under the  Securities  Act of all  Registerable  Securities;  provided,
         however,  that a Holder  of  Registerable  Securities  may  inform  the
         Company  in writing  that it wishes to exclude  all or a portion of its
         Registerable  Securities from such  registration  and upon such notice,
         such Registerable Securities shall be excluded from such registration.

                           (i) The  holders of a  majority  in  interest  of the
                  Registerable  Securities  shall  have the right to select  the
                  managing underwriters, if any, and to approve the terms of the
                  underwriting   agreement  in  respect  of  such  registration,
                  subject to the  approval  of the  Company,  which shall not be
                  unreasonably withheld.

                           (iii) The  Company  is  obligated  to use good  faith
                  efforts to effect only one such registration  pursuant to this
                  Section 2(a) of this Agreement.

                  (b)      Piggyback Registration
                           ----------------------

                           (i) On an  unlimited  number of  occasions  until the
                  third anniversary of the Closing of the Company's  offering of
                  the  Notes  and  Warrants,  and  subject  to the terms of this
                  Agreement and excluding the Public Offering,  in the event the
                  Company  decides to register any of its common  stock  (either
                  for its own  account or the  account  of a security  holder or
                  holders,  other than in connection  with a registration  being
                  effected pursuant to Section 2(a) above) on an SEC form (other
                  than S-4 or S-8 or successor forms) that would be suitable for
                  a registration involving Registerable Securities,  the Company
                  will: (x) promptly give each Holder of Registerable Securities
                  written   notice  thereof  (which  shall  include  a  list  of
                  jurisdictions  in which the  Company  intends to qualify  such
                  securities  under  the  applicable  Blue  Sky or  other  state
                  securities laws) and (y) include in such  registration (and in
                  any  related  qualification  under  the Blue Sky laws or other
                  state  securities  laws),  and  in any  underwriting  involved
                  therein,  all  the  Registerable  Securities  specified  in  a
                  written  request  delivered  to the  Company  by any Holder of
                  Registerable  Securities within 20 days after delivery of such
                  written  notice from the  Company.  Nothing  contained in this
                  Section  2(b)  shall  limit  the  ability  of the  Company  to
                  withdraw a  Registration  Statement it has filed either before
                  or after effectiveness.

                           (ii) If the  registration  of which the Company gives
                  notice pursuant to Section 2(b)(i) is for a registered  public
                  offering  involving  an  underwriting,  the  Company  shall so
                  advise the Holders of Registerable Securities as a part of the
                  written  notice  given  pursuant to Section  2(b)(i).  In such
                  event the right of any Holder of  Registerable  Securities  to
                  registration  shall be conditioned upon such  underwriting and
                  the inclusion of such Holders' Registerable Securities in such
                  underwriting  to the extent provided in this Section 2(b). All
                  Holders of  Registerable  Securities  proposing to  distribute
                  their securities  through such an underwriting shall (together
                  with the  Company  and the other  holders  distributing  their
                  securities   through   such   underwriting)   enter   into  an
                  underwriting  agreement with the Underwriter's  representative
                  for such  offering;  provided  that such holders shall have no
                  right to participate in the selection of the  underwriters for
                  an offering pursuant to this Section 2(b).

                           (iii) In the event the  Underwriters'  representative
                  advises  the  Holders  of  Registerable   Securities   seeking
                  registration  of  Registerable  Securities  pursuant  to  this
                  Section  2(b)  in  writing  that  market  factors  (including,
                  without  limitation,  the aggregate number of shares of common
                  stock requested to be registered, the general condition of the
                  market,  and  the  status  of the  persons  proposing  to sell
                  securities pursuant to this registration) require a limitation


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                  of the number of shares to be underwritten,  the Underwriter's
                  representative may exclude some or all Registerable Securities
                  from such  registration and  underwriting.  In such event, the
                  Underwriters'  representative  shall so advise all  Holders of
                  Registerable   Securities   of  the   number   of   shares  of
                  Registerable   Securities   that  may  be   included  in  such
                  registration  and  underwriting  (if any),  and the  number of
                  shares of Registerable Securities that may be included in such
                  registration  and  underwriting  (if any)  shall be  allocated
                  among all  holders  seeking  registration  in  proportion,  as
                  nearly as practicable,  to the number of shares proposed to be
                  included  in the  registration  by the  Holder.  The number of
                  shares  of  Registerable  Securities  to be  included  in such
                  underwriting  shall not be reduced unless all other securities
                  (other than those sold by the Company) are  similarly  limited
                  from the  underwriting.  No  Registerable  Securities or other
                  securities  excluded from the  underwriting  by reason of this
                  Section 2(b) shall be included in such Registration Statement.

                           (iv) If any Holder of Registerable  Securities,  or a
                  holder  of other  securities  entitled  (upon  request)  to be
                  included in such registration, disapproves of the terms of any
                  underwriting,  such Holder may elect to withdraw  therefrom by
                  written notice to the Company delivered at least 20 days prior
                  to the effective date of the Registration Statement.

         3.  Obligations  of the Company.  When required under this Agreement to
effect the  registration of the Registerable  Securities,  the Company shall, as
expeditiously as reasonably possible, use good faith efforts to:

                  (a) Prepare and file with the SEC a registration  statement or
         statements or similar  documents (the  "Registration  Statement")  with
         respect to all  Registerable  Securities,  other than any  Registerable
         Securities  excluded by Holders of Registerable  Securities pursuant to
         Section 2(a). The Registration  Statement shall be filed not later than
         six months  after the  Closing of the Public  Offering  and the Company
         will use good faith  efforts to cause such  Registration  Statement  to
         become  effective.  The Company will use good faith efforts to keep the
         Registration  Statement  effective  pursuant  to Rule 415 at all  times
         until the  earlier of (i) the third  anniversary  of the final  closing
         date of the Company's  offering of Notes and Warrants to the Investors,
         or  (ii)  the  date  on  which  all  Investors  can  sell  any  of  the
         Registerable  Securities  pursuant  to Rule 144 of the  Securities  Act
         without restriction under Rule 144(e) thereof; provided,  however, that
         if a public offering of common stock by the Company is closed on a date
         that is more than two years  following  the first  date each  Holder of
         Registerable Securities held such Registerable Securities,  the Company
         shall have no obligation to file a Registration Statement in respect of
         such  Registerable  Securities  pursuant  to  this  Agreement,   except
         pursuant to Section 2(b).

                  (b) Prepare and file with the SEC such  amendments  (including
         post-effective   amendments)  and   supplements  to  the   Registration
         Statement and the Prospectus used in connection  with the  Registration
         Statement  as may be  necessary  to  keep  the  Registration  Statement
         effective  at all times until the earlier of (i) the third  anniversary
         of the final  closing date of the  Company's  offering of the Notes and
         Warrants,  or (ii) the  date on  which  all  Investors  can sell  their
         respective  shares of Registerable  Securities  pursuant to Rule 144 of
         the Securities Act without  restriction under Rule 144(e) thereof,  and
         to comply with the provisions of the Securities Act with respect to the
         disposition of all securities covered by the Registration Statement.

                  (c) Furnish promptly to the Holders of Registerable Securities
         such  numbers  of  copies  of a  prospectus,  including  a  preliminary
         prospectus,  and all amendments and supplements  thereto, in conformity
         with the  requirements  of the Securities Act, and such other documents
         as the Holders of  Registerable  Securities may  reasonably  request in
         order to facilitate the disposition of Registerable Securities.

                  (d)  Register  and  qualify  the  securities  covered  by  the


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         Registration  Statement under such other securities or Blue Sky laws of
         such  jurisdictions  as shall be reasonably  requested by the Investors
         and prepare and file in those jurisdictions such amendments  (including
         post-effective  amendments)  and  supplements  and to take  such  other
         actions  as  may  be  necessary  to  maintain  such   registration  and
         qualification in effect at all times until the earlier of (i) the third
         anniversary  of the final  closing date of the Company  offering of the
         Notes and  Warrants,  or (ii) the date on which all  Investors can sell
         their respective shares of Registerable Securities pursuant to Rule 144
         of the Securities Act with out  restriction  under Rule 144(e) thereof,
         and to take all other  actions  necessary  or  advisable  to enable the
         disposition of such securities in such jurisdictions, provided that the
         Company shall not be required in connection therewith or as a condition
         thereto  to  qualify  to do  business  or to file a general  consent to
         service of process in any such  states or  jurisdictions  or to provide
         any  undertaking  or make any change in its charter or bylaws which the
         Board of Directors  determines  to be contrary to the best  interest of
         the Company and its stockholders.

                  (e) In the event the  holders of a majority in interest of the
         Registerable  Securities  select  underwriters for the offering,  enter
         into and perform its obligations  under an underwriting  agreement,  in
         usual and customary  form,  including,  without  limitation,  customary
         indemnification  and  contribution   obligations,   with  the  managing
         underwriter of such offering.  The Investors  shall also enter into and
         perform their customary obligations under any such agreement including,
         without   limitation,   customary   indemnification   and  contribution
         obligations.

                  (f) Notify the Holders of Registerable Securities, at any time
         when a prospectus  relating to Registerable  Securities  covered by the
         Registration Statement is required to be delivered under the Securities
         Act, of the happening of any event as a result of which the  prospectus
         included in the Registration  Statement, as then in effect, includes an
         untrue  statement of a material  fact or omits to state a material fact
         required  to be stated  therein  or  necessary  to make the  statements
         therein not misleading in light of the circumstances then existing. The
         Company shall promptly amend or supplement the  Registration  Statement
         to correct any such untrue statement or omission.

                  (g)  Notify  the  Holders of  Registerable  Securities  of the
         issuance by the SEC of any stop order  suspending the  effectiveness of
         the Registration Statement or the initiation of any proceedings for the
         purposes.  The Company will make every reasonable effort to prevent the
         issuance of any stop order and, if any stop order is issued,  to obtain
         the lifting thereof at the earliest possible time.

                  (h)  Permit a single  firm of  counsel  designated  as selling
         stockholders'  counsel by the  holders of a majority in interest of the
         Registerable Securities commencing at a reasonable period of time prior
         to  their  filing,  to  review  the  Registration   Statement  and  all
         amendments and supplements thereto and shall not file any document in a
         form to which such counsel reasonably objects.

                  (i) Make generally  available to its security  holders as soon
         as  practicable,  but not  later  than 90 days  after  the close of the
         period covered thereby,  an earnings  statement (in form complying with
         the  provisions  of Rule 158  under  the  Securities  Act)  covering  a
         12-month period beginning not later than the first day of the Company's
         fiscal quarter next  following the effective  date of the  Registration
         Statement.

                  (j) At the request of the Holders of Registerable  Securities,
         furnish to the  underwriters on the date that  Registerable  Securities
         are  delivered  to the  underwriters  for  sale  in  connection  with a
         registration  pursuant to this  Agreement  (i) an  opinion,  dated such
         date, of the counsel  representing the Company for the purposes of such
         registration,  in  form  and  substance  as  is  customarily  given  to
         underwriters  in an  underwritten  public  offering,  addressed  to the
         underwriters,  and (ii) a letter dated such date,  from the independent
         certified public  accountants of the Company,  in form and substance as
         is customarily  given by independent  certified  public  accountants to
         underwriters  in an  underwritten  public  offering,  addressed  to the
         underwriters.


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                  (k)  Make   available   for   inspection  by  the  Holders  of
         Registerable Securities, any underwriters participating in the offering
         pursuant to the registration and the counsel, accountants or

         other agents  retained by the  Investors,  all pertinent  financial and
         other records,  corporate documents and properties of the Company,  and
         cause the  Company's  officers,  directors  and employees to supply all
         information  reasonably  requested by the Investors in connection  with
         the registration.

                  (l)  If  the  Common  Stock  is  then  listed  on  a  national
         securities exchange,  cause the Registerable Securities to be listed on
         such  exchange.  If the Common  Stock is not then  listed on a national
         securities exchange, use good faith efforts to facilitate the reporting
         of the Common Stock on NASDAQ.

                  (m)  Provide a transfer  agent and  registrar,  which may be a
         single  entity,  for the  Registerable  Securities  not later  than the
         effective date of the Registration Statement.

                  (n)  Take all  actions  necessary  to  facilitate  the  timely
         preparation and delivery of  certificates  (not bearing any restrictive
         legend) representing the Registerable Securities to be sold pursuant to
         the  Registration  Statement and to enable such  certificates  to be in
         such  denominations and registered in such names as the Holders of such
         Registerable Securities or any underwriters may reasonably request.

                  (o) Take all other  reasonable  actions  necessary to expedite
         and  facilitate  disposition  by  the  Investors  of  the  Registerable
         Securities pursuant to the Registration Statement.

         4.  Furnish  Information.  It shall  be a  condition  precedent  to the
obligations  of the Company to take any action  pursuant to this  Agreement with
respect to each Investor  that such  Investor  shall furnish to the Company such
information  regarding itself,  the Registerable  Securities held by it, and the
intended  method  of  disposition  of such  securities  as shall  be  reasonably
required to effect the  registration  of the  Registerable  Securities and shall
execute such documents in connection  with such  registration as the Company may
reasonably request.

         5. Expenses of Registration.  All expenses  incurred in connection with
registration,  filings or qualifications pursuant to Sections 2 and 3, including
without limitation,  all registration,  listing,  filing and qualification fees,
printers and  accounting  fees,  the fees and  disbursements  of counsel for the
Company  and the  reasonable  fees  and  disbursements  of one  counsel  for the
Investors  shall be borne by the  Company  (except in the case of the  automatic
registration  pursuant  to  Section  2(a) for which  underwriter  discounts  and
commissions shall not be borne by the Company).

         6.  Indemnification.  In the  event  any  Registerable  Securities  are
included in a Registration Statement:

                  (a) To the extent permitted by law, the Company will indemnify
         and hold harmless each Investor, the directors,  employees,  agents and
         the  officers of the  Company,  each person who signs the  Registration
         Statement,  and each person,  if any,  who  controls  any of them,  any
         underwriter  (as  defined in the  Securities  Act) for such  Holders of
         Registerable  Securities and each person, if any, who controls any such
         underwriter  within the meaning of the Securities Act or the Securities
         Exchange Act of 1934, as amended (the "1934 Act"),  against any losses,
         claims,  damages,  expenses or liabilities  (or actions or proceedings,
         whether commenced or threatened,  in respect thereof) arising out of or
         based upon any of the  following  statements,  omissions or  violations
         (collectively,  a  "Violation"):  (i) any untrue  statement  or alleged
         untrue  statement  of a material  fact  contained  in the  Registration
         Statement,  including any  preliminary  prospectus or final  prospectus
         contained  therein or any amendments or supplements  thereto,  (ii) the
         omission or alleged  omission to state therein a material fact required
         to be stated therein,  or necessary to make the statements  therein, in
         light of the circumstances in which they were made, not misleading,  or
         (iii)  any  violation  or  alleged  violation  by  the  Company  of the


                                       C-5



         Securities Act, the 1934 Act, any state  securities laws or any rule or
         regulation  promulgated  under the Securities  Act, the 1934 Act or any
         state securities laws; and the Company will reimburse the Investors and
         each such underwriter or controlling person,  promptly as such expenses
         are incurred, for any legal or other expenses reasonably
         incurred by them in connection with investigating or defending any such
         loss,  claim,  damage,  liability,  action  or  proceeding;   provided,
         however,  that the indemnity  agreement  contained in this Section 6(a)
         shall not apply to amounts paid in settlement of any such loss,  claim,
         damage,  liability or action if such settlement is effected without the
         consent  of the  Company,  which  consent  shall  not  be  unreasonably
         withheld, nor shall the Company be liable in any such case for any such
         loss, claim, damage,  liability, or action to the extent that it arises
         out of or is based upon a Violation  which occurs in reliance  upon and
         in conformity with written  information  furnished expressly for use in
         connection  with  such  registration  by  the  Investors  or  any  such
         underwriter or controlling  person,  as the case may be. Such indemnity
         shall remain in full force and effect  regardless of any  investigation
         made by or on  behalf  of the  Investors  or any  such  underwriter  or
         controlling  person and shall survive the transfer of the  Registerable
         Securities by the Holders of Registerable Securities.

                  (b)  To  the  extent   permitted   by  law,   each  Holder  of
         Registerable Securities,  severally and not jointly, will indemnify and
         hold harmless the Company, each of its directors,  each of its officers
         who have signed the Registration  Statement,  each person,  if any, who
         controls the Company  within the meaning of the  Securities  Act or the
         1934 Act, any underwriter and any other stockholder  selling securities
         pursuant  to the  Registration  Statement  of any of its  directors  or
         officers or any person who controls such holder or underwriter, against
         any losses,  claims, damages of liabilities (joint or several) to which
         any of them may become subject,  under the Securities Act, the 1934 Act
         of other federal or state law, insofar as such losses,  claims, damages
         or  liabilities  (or  actions in respect  thereof)  arise out of or are
         based upon any  Violation,  in each case to the extent (and only to the
         extent) that such  Violation  occurs in reliance upon and in conformity
         with  written  information  furnished  by such  Holder of  Registerable
         Securities expressly for use in connection with such registration;  and
         such Holder of  Registerable  Securities  will  reimburse  any legal or
         other expenses  reasonably  incurred by any of them in connection  with
         investigating or defending any such loss, claim,  damage,  liability or
         action;  provided,  however,  that the indemnity agreement contained in
         this Section 6(b) shall not apply to amounts paid in  settlement of any
         such loss,  claim,  damage,  liability or action if such  settlement is
         effected without the consent of such Holder of Registerable Securities,
         which  consent  shall  not  be  unreasonably  withheld;  and  provided,
         further,  that the Investor  shall be liable under this  paragraph  for
         only that amount of losses, claims, damages and liabilities as does not
         exceed  the  proceeds  to such  Investor  as a  result  of the  sale of
         Registerable Securities pursuant to such registration.

                  (c) Promptly after receipt by an indemnified  party under this
         Section 6 of notice of the  commencement  of any action  (including any
         governmental  action),  such  indemnified  party  will,  if a claim  in
         respect thereof is to be made against any indemnifying party under this
         Section 6, deliver to the  indemnifying  party a written  notice of the
         commencement thereof and the indemnifying party shall have the right to
         participate in, and, to the extent the  indemnifying  party so desires,
         jointly with any other indemnifying party similarly noticed,  to assume
         control of the defense  thereof with counsel  mutually  satisfactory to
         the parties;  provided,  however,  than an indemnified party shall have
         the right to retain its own  counsel,  with the fees and expenses to be
         paid by the  indemnifying  party,  if,  in the  reasonable  opinion  of
         counsel for the indemnifying party,  representation of such indemnified
         party by the  counsel  retained  by the  indemnifying  party,  would be
         inappropriate  due to actual or potential  differing  interests between
         such indemnified  party and any other party represented by such counsel
         in such  proceeding.  The  failure  to  deliver  written  notice to the
         indemnifying  party within a reasonable time of the commencement of any
         such action shall relieve such  indemnifying  party of any liability to
         the  indemnified  party  under  this  Section  6  only  to  the  extent
         prejudicial  to its ability to defend such action,  but the omission so
         to deliver written notice to the indemnifying party will not relieve it
         of any liability that it may have to any  indemnified  party  otherwise
         than under this Section 6. The indemnification required by this Section


                                      C-6

         6 shall be made by periodic  payments of the amount  thereof during the
         course of the investigation or defense, promptly as such expense, loss,
         damage or liability is incurred.

                  (d) To the extent any indemnification by an indemnifying party
         is prohibited or limited by law, the indemnifying  party agrees to make
         the maximum contribution with respect to any amounts for which it would
         otherwise  be liable  under this  Section 6 to the extent  permitted by
         law,   provided   that  (i)  no   contribution   shall  be  made  under
         circumstances   where  the  maker   would  not  have  been  liable  for
         indemnification  under the fault standards set forth in this Section 6,
         (ii)  no  seller  of  Registerable   Securities  guilty  of  fraudulent
         misrepresentation   (within  the  meaning  of  Section   11(f)  of  the
         Securities  Act) shall be entitled to  contribution  from any seller of
         Registerable   Securities  who  was  not  guilty  of  such   fraudulent
         misrepresentation, and (iii) contribution by any seller of Registerable
         Securities  shall be limited  in amount to the net  amount of  proceeds
         received by such seller from the sale of such Registerable Securities.

         7. Reports Under Securities Exchange Act of 1934. With a view to making
available to the Holders of Registerable Securities the benefits of SEC Rule 144
promulgated under the Securities Act and any other rule or regulation of the SEC
that may at any time permit the  Investors to sell  securities of the Company to
the public without registration, the Company agrees to:

                  (a) make and keep public information available, as those terms
         are understood and defined in SEC Rule 144, at all times;

                  (b) file with the SEC in a timely manner all reports and other
         documents required of the Company under the Securities Act and the 1934
         Act; and

                  (c) furnish to each Holder of Registerable Securities, so long
         as  such  Holder  of  Registerable  Securities  owns  any  Registerable
         Securities,  forthwith  upon  request  (i) a written  statement  by the
         Company that it has complied  with the  reporting  requirements  of SEC
         Rule 144, the  Securities Act and the 1934 Act, (ii) a copy of the most
         recent annual or quarterly report of the Company and such other reports
         and documents so filed by the Company, and )iii) such other information
         as may be reasonably requested in availing the Investors of any rule or
         regulation of the SEC which permits the selling of any such  securities
         without registration.

         8.  Assignment of Registration  Rights.  The rights to have the Company
register  Registerable  Securities pursuant to this Agreement may be assigned by
the  Holders  of  Registerable  Securities,  subject  to  the  Holders  of  such
Registerable  Securities and such assignment  being in compliance with the terms
of this Agreement and any agreements  incorporated  herein,  and subject to such
assignment  being in conformity with federal and state securities law, rules and
regulations,  unless exempt  therefrom;  to  transferees  or assignees,  of such
securities  provided such  transferee or assignee within a reasonable time after
such transfer,  furnishes the Company  written notice of the name and address of
such  transferee  or  assignee  and the  securities  with  respect to which such
registration rights are being assigned;  provided, further, that such assignment
shall be  effective  only if  immediately  following  such  transfer the further
disposition of such securities by the transferee or assignee is restricted under
the Securities  Act. The term "Investor" as used in this Agreement shall include
permitted assignees.

         9.       Miscellaneous.
                  --------------

                  (a) Notices  required or permitted to be given hereunder shall
         be in  writing  and  shall be  deemed  to be  sufficiently  given  when
         personally  delivered  or  sent  by  registered  mail,   return-receipt
         request,  addressed (i) if to the Company at Cheung Laboratories,  Inc.
         c/o Augustine Cheung,  PhD.,  Chairman of the Board and Chief Executive

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         Office at 10220-I Old Columbia Road, Columbia, Maryland 21046-1705, and
         (ii) if to an Investor,  at the address set forth under his name in the
         Subscription  Agreement,  or at such  other  address as each such party
         shall furnish by notice given in accordance with this Section 9(a).

                  (b) Failure of any party to exercise any right or remedy under
         this  Agreement or otherwise,  or delay by a party in  exercising  such
         right to remedy,  will not operate as a waiver thereof.  No waiver will
         be effective  unless and until it is in writing and signed by the party
         giving the waiver.

                  (c) The Agreement shall be enforced, governed and construed in
         all respects in accordance  with the laws of the State of Maryland,  as
         such laws are applied by Maryland courts to agreements entered into and
         to be  performed in Maryland by and between  residents of Maryland.  In
         the  event  that  any  provision  of  this   Agreement  is  invalid  or
         unenforceable  under any  applicable  statute or rule of law, then such
         provision  shall  be  deemed  inoperative  to the  extent  that  it may
         conflict  therewith  and shall be deemed  modified to conform with such
         statute or rule of law. Any provision hereof which may prove invalid or
         unenforceable   under  any  law  shall  not  affect  the   validity  or
         enforceability of any other provision hereof.

                  (d) The Company  will not,  after the date of this  Agreement,
         enter  into any  agreement  with  respect  to its  securities  which is
         inconsistent  with the rights  granted to the  Holders of  Registerable
         Securities in this Agreement or otherwise conflicts with the provisions
         hereof.

                  (e) The provisions of this Agreement, including the provisions
         of this sentence,  may not be amended,  modified or  supplemented,  and
         waivers or consents to departures from the provisions hereof may not be
         given unless the Company has obtained the written consent of holders of
         at  least  a  majority  of  shares  of  the  Registerable   Securities.
         Notwithstanding  the  foregoing,  a waiver or consent to departure from
         the   provisions   hereof  with  respect  to  a  matter  which  relates
         exclusively to the rights of Holders of Registerable  Securities  whose
         securities  are being sold  pursuant to a  Registration  Statement  and
         which  does not  directly  or  indirectly  affect  the  rights of other
         Holders of  Registerable  Securities  may be given by the  holders of a
         majority  of the shares of the  Registerable  Securities  being sold by
         such holders,  provided that the provisions of this sentence may not be
         amended,  modified,  or  supplemented  except  in  accordance  with the
         provisions of the immediately preceding sentence.

                  (f) Subject to Section 8 hereof, this Agreement shall inure to
         the benefit of and be binding upon the successors and permitted assigns
         of each of the parties,  including  without  limitation and without the
         need for an express  assignment,  subsequent  holders  of  Registerable
         Securities.

                  (g)  This   Agreement   may  be  executed  in  any  number  of
         counterparts and by the parties hereto in separate  counterparts and by
         facsimile signatures, each of which when so executed shall be deemed to
         be an original and all of which taken together shall constitute one and
         the same agreement.

                  (h) This  Agreement  is  intended  by the  parties  as a final
         expression  of  their  agreement  and  intended  to be a  complete  and
         exclusive  statement of the agreement and  understanding of the parties
         hereto in respect of the subject matter contained herein.  There are no
         restrictions,  promises,  warranties or undertakings,  other than those
         set forth or referred to herein with respect to the registration rights
         granted  by  the  Company  with  respect  to  the  securities  sold  in
         connection  with the  Offering.  This  Agreement  supersedes  all prior
         agreements and  understanding  between the parties with respect to such
         subject matters.

                                       C-8




Dated this ____ day of __________ 19_____.

INVESTOR:                          CHEUNG LABORATORIES, INC.



__________________                 By: _________________________________________
Signature




__________________                 Title: ______________________________________
Printed Name


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