BIOROYALTIES, L.L.C.

                                                                      Exhibit 1

                                    AGREEMENT

      Pursuant to Rule 13d-1(k) under the Securities Act of 1934, as amended,
the undersigned hereby agree that only one statement containing the information
required by Schedule 13D needs be filed with respect to the ownership by each of
the undersigned of Units of Limited Partnership Interest of PaineWebber R&D
Partners II, L.P.

Dated: February 23, 1999


                                  BIOROYALTIES, L.L.C.

                                  By: /s/ XXXXX XXXXXXXXX
                                     -----------------------------------
                                  Name:   Xxxxx Xxxxxxxxx
                                  Title:  Managing Member of Pharmaceutical
                                          Partners, L.L.C., the Manager


                                  PHARMACEUTICAL ROYALTIES, L.L.C.

                                  By: /s/ XXXXX XXXXXXXXX
                                     -----------------------------------
                                  Name:   Xxxxx Xxxxxxxxx
                                  Title:  Managing Member of Pharmaceutical
                                          Partners, L.L.C., the Manager


                                  PHARMACEUTICAL ROYALTY INVESTMENTS LTD.

                                  By: /s/ XXXXX XXXXXX
                                     -----------------------------------
                                  Name:   Xxxxx Xxxxxx
                                  Title:  Managing Member of Pharmaceutical
                                          Partners, L.L.C., the Manager


                                  BIOVENTURE INVESTMENTS, KFT

                                  By: /s/ XXXXX XXXXXX
                                     -----------------------------------
                                  Name:   Xxxxx Xxxxxx
                                  Title:  Managing Member of Pharmaceutical
                                          Partners, L.L.C., the Manager


                                  PHARMACEUTICAL PARTNERS, L.L.C.

                                  By: /s/ XXXXX XXXXXXXXX
                                     -----------------------------------
                                  Name:  Xxxxx Xxxxxxxxx
                                  Title: Managing Member






                                     /S/ XXXXXXX XXXXX-FREKE
                                     -----------------------------------
                                     Name: Xxxxxxx Xxxxx-Freke


                                     /S/ XXXXX XXXXXXXXX
                                     -----------------------------------
                                     Name: Xxxxx Xxxxxxxxx


                                     /S/ XXXXX XXXXXX
                                     -----------------------------------
                                     Name: Xxxxx Xxxxxx


                                     /S/ XXXX XXXXX
                                     -----------------------------------
                                     Name: Xxxx Xxxxx