Xoma Ltd., of Berkeley, Calif., presented data at the 59th annual meeting of the American Academy of Dermatology in Washington on two clinical studies of Xanelim in patients with moderate to severe plaque psoriasis.
Xanelim, co-developed with Genentech Inc., of South San Francisco, is in Phase III trials for moderate to severe psoriasis and Phase I/II for kidney transplant rejection.
In a Phase I/II open-label study, 61 patients were given an initial subcutaneous conditioning dose of 0.7 mg/kg of Xanelim, followed by 11 weekly subcutaneous treatments of 1 mg/kg, 2 mg/kg or 4 mg/kg. The primary response measure was change in Psoriasis Area and Severity Index (PASI) scores between days 0 and 84. Overall, 75 percent of patients given Xanelim achieved 50 percent or better PASI improvement at day 84 and 31 percent achieved 75 percent or better improvement. The drug was well tolerated in the majority of patients and the most commonly observed adverse side effects were headache, flu-like symptoms and psoriasis symptoms after completion of treatment.
Researchers also presented preliminary results from a 12-week open-label study running parallel to the Phase III program. The new study retreated patients who received IV or subcutaneous Xanelim in Phase I or II studies. Patients received an initial subcutaneous conditioning dose of 0.7 mg/kg of Xanelim, followed by 11 weekly doses of 1.0 mg/kg or 2.0 mg/kg. Some patients received topical steroids, calcipotriene or UVB phototherapy concurrently with Xanelim. Overall, almost 80 percent of patients achieved a comparable or better PASI score at the end of the second course of treatment compared to the first course. At the end of treatment, 28 percent of patients achieved 75 percent or better PASI improvement and 58 percent achieved 50 percent or better.
Xoma's stock (NASDAQ:XOMA) rose 43.7 cents Monday, or about 5.5 percent, to close at $8.312.
In other news from the meeting:
Abgenix Inc., of Fremont, Calif., presented results of its double-blind, placebo-controlled Phase IIa trial of ABX-IL8, its fully human monoclonal antibody, for use in the treatment of moderate to severe psoriasis. The study included 94 patients at 18 sites in the United States and assessed 3 mg/kg and 6 mg/kg doses. The drug was administered every three weeks for a total of five infusions, with the first dose being a 2x loading dose. Results showed that ABX-IL8 (3 mg/kg) was associated with a statistically significant improvement in plaque psoriasis as assessed by change in baseline PASI scores and physician global assessments. The 6 mg/kg dose was not statistically significantly different from the 3 mg/kg dose. Also, patients who achieved a 75 percent improvement in PASI maintained that response through week 36. Based on the Phase IIa data, Abgenix has initiated a Phase IIb study that should enroll 228 patients and will evaluate two doses of ABX-IL8 and a placebo.
Biogen Inc., of Cambridge, Mass., said retreatment with Amevive (alefacept) in patients with moderate to severe chronic plaque psoriasis demonstrated positive results similar to that of the initial course of treatment, an earlier Phase II randomized, placebo-controlled, double-blind, multiple-dose study. The retreatment study is ongoing and is designed to determine the tolerability and efficacy of repeated courses of treatment with Amevive. Patients received two courses of study therapy and clinical response was evaluated at two weeks after dosing using the PASI. Responses were observed within the first four weeks and tended to be more rapid with the second course of treatment. There were no reports of disease rebound.
IDEC Pharmaceuticals Corp., of San Diego, presented results from a multiple-dose Phase I/II trial of IDEC-114, its primatized anti-CD80 (anti-B7-1) monoclonal antibody, in patients with moderate to severe psoriasis. Thirty-five patients received four infusions of the drug at a variety of dosage levels. It was reported that 40 percent of patients achieved the clinical endpoint of at least a 50 percent reduction in PASI at some point of the study and 57 percent of patients achieved a physician's global psoriasis assessment of good or above. Also, although treatment ended on day 47, patients continued to improve beyond that, with maximum improvements in PASI scores seen on the last follow-up day, which was day 127.