Exhibit 99.1


                             Joint Filing Agreement

      The undersigned hereby agree that this Amendment No. 2 to Schedule 13G (as
so amended, the "Schedule 13G") with respect to the common stock of Transition
Therapeutics Inc. is, and any additional amendment thereto signed by each of the
undersigned shall be, filed on behalf of each undersigned pursuant to and in
accordance with the provisions of 13d-1(k) under the Securities Exchange Act of
1934, as amended, and that all subsequent amendments to the Schedule 13G shall
be filed on behalf of each of the undersigned without the necessity of filing
additional joint filing agreements. The undersigned acknowledge that each shall
be responsible for the timely filing of such amendments, and for the
completeness and accuracy of the information concerning it contained therein,
but shall not be responsible for the completeness and accuracy of the
information concerning the other, except to the extent that it knows or has
reason to believe that such information is inaccurate.

Dated:  May 20, 2009


                                             /s/ Larry N. Feinberg
                                             --------------------------------
                                             Larry N. Feinberg



                                             ORACLE ASSOCIATES, LLC




                                             By:  /s/ Larry N. Feinberg
                                                  ------------------------------
                                                  Name:   Larry N. Feinberg
                                                  Title:  Senior Managing Member