Allergan Announces Results of Its Oral Tazarotene Phase Three Studies; Results Presented at the Winter AAD

Business Wire, March 24, 2003

Business Editors/Health/Medical Writers

IRVINE, Calif.--(BUSINESS WIRE)--March 24, 2003

Allergan, Inc. (NYSE:AGN) announced today the results of its two Phase 3 trials of an oral gel-capsule formulation of tazarotene in the treatment of moderate to severe psoriasis. The data was presented by Dr. John Koo, Professor and Vice-Chairman of the University of San Francisco Department of Dermatology at the 2003 American Academy of Dermatology meeting in San Francisco, California. The trials were multi-center, double-blind, randomized, placebo-controlled, safety and efficacy studies of 12 weeks treatment with oral tazarotene 4.5 mg followed by 12 weeks post-treatment follow-up.

There were two clinical measures used to evaluate patients in the study, overall lesional assessment (OLA) and overall global response to treatment. OLA is an integrated clinical assessment of disease severity. Physicians were provided with photonumeric guidelines to ensure evaluation consistency across study sites.

Based on an integrated analysis of the two clinical trials, more than 50% (53.8%) of patients achieved global treatment success of at least 50% improvement and 29.7% of patients treated with oral tazarotene achieved at least 75% improvement compared with 14.9% and 7.4%, respectively, in patients receiving placebo. These results were significant at p less than 0.001. Also at week 12, 17% of patients treated with oral tazarotene had clinical success with an OLA of none or minimal psoriasis compared with only 3% treated with placebo (p less than 0.001).

"I'm pleased with the results of these clinical studies and excited about the possibility that a new retinoid therapy could be available to patients suffering from psoriasis," said Dr. Koo. "Based on the outstanding results and the efficacy demonstrated in this trial, oral tazarotene may provide physicians an exciting new therapy to increase patient results."

Patients were evaluated at baseline and weeks 1, 2, 4, 8 and 12 (the treatment phase) and weeks 16, 20 and 24 (the post-treatment phase). As is consistent with retinoid therapy, women of childbearing potential were required to be on appropriate contraception because of the teratogenic risks. The primary efficacy endpoint for the trials was the achievement of clinical success, defined as an OLA of none or minimal disease based on the 6 point OLA score (0=none, 1=minimal, 2=mild, 3=moderate, 4=severe, 5=very severe disease). In the combined analysis of the two phase 3 trials, 340 patients were treated with oral tazarotene and 350 with placebo. At the start of the study, patients had a mean OLA score of 3.4 (moderate to severe) and approximately 29% body surface area affected. The trial results show that oral tazarotene met the primary efficacy endpoints. These studies also suggest there may be duration of relief of disease after discontinuation of treatment.

These results were achieved in the absence of any consistent, clinically significant changes in laboratory values including serum triglycerides, total cholesterol, HDL cholesterol, liver function and hematology tests. The only statistically significant adverse events observed in the tazarotene-treated patients vs. placebo, with an incidence equal to or greater than 5%, were cheilitis (66% vs. 17%), dry skin (24% vs. 15%), headache (19% vs. 12%), arthralgia (17% vs. 8%), myalgia (14% vs. 8%) and back pain (7% vs. 3%). No treatment-related serious adverse events were observed. Less than 5% of patients on treatment discontinued the study due to adverse events.

In these trials, there were no consistent clinically significant changes in laboratory values. This may be attributable to tazarotene's retinoid receptor selectivity.

Allergan intends to file for approval with the U.S. Food and Drug Administration in the second half of 2003. Tazarotene is currently marketed in the United States as topical formulations under the trade names TAZORAC(R) 0.1% and 0.5% and AVAGE(TM) 0.1%.

Forward-Looking Statements

Any of the above statements that refer to the Company's estimated or anticipated future results are forward-looking and reflect the Company's current analysis of existing trends and information. Actual results may differ from current expectations based on a number of factors affecting Allergan's businesses, including the inherent uncertainties associated with the research and development process and the regulatory approval process, technological advances and patents attained by competitors, competitive conditions and changing market conditions, including the performance and acceptance of new products. Accordingly, no assurance can be given that the Company will receive FDA approval to market Oral Tazarotene, or that, if approved, the Company will be able to successfully launch and market the product. These forward-looking statements represent the Company's judgment only as of the date of this press release. Actual results could differ materially from those projected in this release. As a result, the reader is cautioned not to rely on these forward-looking statements. The Company disclaims, however, any intent or obligation to update these forward-looking statements. Additional information concerning these and other risk factors can be found in press releases issued by Allergan as well as Allergan's public periodic filings with the Securities and Exchange Commission, including the discussion under the heading "Certain Factors and Trends Affecting Allergan and its Businesses" in Allergan's Form 10-K for the year ended December 31, 2002. Copies of Allergan press releases and additional information about Allergan are available on the World Wide Web at www.allergan.com, or you can contact the Allergan Investor Relations Department by calling 714-246-4636.