EXHIBIT 8.1

           [LETTERHEAD OF HELLER EHRMAN WHITE & MCAULIFF, ATTORNEYS]

                               September 5, 1997



Crescendo Pharmaceuticals Corporation
1454 Page Mill Road
Palo Alto, California 94303

     Re:  REGISTRATION STATEMENT ON FORM S-1

Dear Ladies and Gentlemen:

     We have acted as United States federal income tax counsel to Crescendo
Pharmaceuticals Corporation, a Delaware corporation ("Crescendo"), in connection
with the registration under the Securities Act of 1933, as amended, of 5,800,000
shares of Crescendo's Class A Common Stock (the "Shares").  In that capacity, we
have examined the Registration Statement on Form S-1 (the "Registration
Statement") filed by Crescendo with the Securities and Exchange Commission in
connection with the proposed distribution of the Shares by ALZA Corporation.

     We hereby confirm our opinion contained in the Registration Statement
under the caption "Federal Income Tax Considerations."

     The foregoing is based on the Internal Revenue Code of 1986, as amended
(the "Code"), Treasury Regulations (including proposed Treasury Regulations)
promulgated thereunder, rulings, official pronouncements and judicial decisions,
all as in effect on the date hereof and all of which are subject to change or
different interpretations by the Internal Revenue Service or the courts, which
change may have retroactive effect.  We disclaim any undertaking to advise you
of any change in the law that may affect this opinion.  We express no opinion as
to the laws of any jurisdictions other than the federal income tax laws of the
United States of America.

 
Crescendo Pharmaceuticals Corporation
September 5, 1997
Page 2


     We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and further consent to the reference to our firm under
the captions "Federal Income Tax Considerations" and  "Legal Matters" in the
Registration Statement and the Prospectus which forms a part thereof.


                                      Very truly yours,



                                      /s/ Heller Ehrman White & McAuliffe



36421.02.PA