Protein Design Labs Inc. (PDL) said development partner Hoffmann-La Roche Inc. started Phase III trials of PDL's Smart Anti-TacAntibody for prevention of acute kidney transplant rejection.

Roche, of Nutley, N.J., expects to enroll more than 250 patients in arandomized, double-blind, placebo-controlled study at 17 centersworldwide. Another Phase III trial for the product, which Roche callsZenapax, is scheduled to begin this quarter.

The primary endpoint is reduction in acute rejection episodes in thesix months following kidney transplantation.

Cary Queen, PDL's vice president of research, said enrollmentshould be completed in six months.

Zenapax is a humanized monoclonal antibody that binds to theinterleukin-2 (IL-2) receptor, which is expressed on activated T cells.It blocks the binding to these cells of IL-2. Results from a multiple-dose Phase I study of the drug will be presented May 16 in Chicagoat the meeting of the American Society of Transplant Physicians.

PDL's stock (NASDAQ:PDLI) was unchanged after Monday'sannouncement. The stock closed up 75 cents Tuesday at $21.50. _Jim Shrine

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