MacroChem announces favorable results of a Phase II clinical trial of SEPA-ibuprofen topical formulation for treating muscular pain.

LEXINGTON, Mass.--(HealthWire)--July 16, 1996--MacroChem Corporation (NASDAQ: MCHM) announced today the results of a Phase II clinical trial of its SEPA(R)-ibuprofen formulation as a topically applied analgesic.

Analysis of the placebo-controlled, double-blind trial in individuals with muscle pain revealed clinically significant analgesic activity following treatment with a topical gel formulation of ibuprofen, a nonsteroidal antiinflammatory agent, containing MacroChem's patented skin absorption enhancer SEPA(R).

Three hundred and fifty subjects participated in the Phase II randomized, double-blind, placebo-controlled study. Subjects were divided into four treatment groups: placebo, placebo + SEPA, 5% ibuprofen, and 5% ibuprofen + SEPA. Treatments were delivered by topical application to the triceps area of normal volunteers 48 hours after strenuous exercise, designed to induce muscle pain and restricted motion. Clinically significant analgesic activity, lasting throughout the five hour measurement period, was observed 30 minutes following application of the SEPA-ibuprofen formulation to subjects experiencing severe pain and was statistically significantly (p=.05) higher (23%) than placebo one hour after dosing. Restricted mobility of the triceps was improved more than two-fold from pretreatment baseline by SEPA-ibuprofen treatment, a 105% greater change than seen in the placebo group. The SEPA-ibuprofen formulation was found to provide greater mean analgesic effects than a formulation of ibuprofen alone. The formulation of ibuprofen without SEPA improved analgesic scores 120 minutes after dosing, compared to placebo, but the response did not reach the levels attained by the SEPA-ibuprofen treated group, and were not statistically significant at any time. The ibuprofen formulation without SEPA is comparable to a product approved for marketing in Europe. No significant treatment-related side effects were reported in any group.

"The results of this study are positive, and provide the stimulus to expand our clinical development program to further test ibuprofen and other related analgesics in topical formulations for treatment of localized pain sites. The completed study employed a robust model of severe, exercise-induced muscle pain, and offered a difficult hurdle for testing of a topical analgesic formulation. The finding of analgesic activity in this stringent model serves as a prelude to future evaluation of SEPA containing formulations in treating spontaneous pain, such as osteoarthritis and rheumatoid arthritis," said Dr. Carlos M. Samour, Chairman and Scientific Director of MacroChem.

The U.S. analgesic market was $8.0 billion in 1995, $3.5 billion of which resulted from sales of ibuprofen and other NSAIDs. "We are pleased that the results of the Phase II study support previous findings establishing the ability of SEPA to enhance the transport of drugs through the skin. The findings from this trial provide a major impetus to continue the clinical development program of SEPA-ibuprofen and other NSAIDs towards regulatory approval. The ability to deliver NSAIDs transdermally to the site of the pain offers the distinct advantage of minimizing systemic blood levels of the active drug, promising to avoid side effects, such as gastrointestinal irritation, and provide more rapid and longer lasting analgesia. An effective topical formulation of an NSAID product would offer a competitive advantage in the huge analgesic market. Currently, no topical NSAID product is approved for marketing in the U.S. With the positive results of the Phase II study in hand, MacroChem will seek strategic alliances with major pharmaceutical companies to complete the development and to market a SEPA-NSAID topical product in the large analgesic drug category," said Alvin J. Karloff, president and chief executive officer of MacroChem.

Certain statements in this release are forward-looking and are based on MacroChem's current expectations. The actual activities and results may differ materially. The reader is referred to "Risk Factors" in MacroChem's latest annual report on Form 10-K for information on the factors that could affect MacroChem's actual results.

MacroChem develops, licenses and markets products and technology for the transdermal and topical delivery of agents used for prescription and OTC pharmaceutical and cosmetic applications. The company's patented SEPA(R) compound, a penetration enhancer for transdermal delivery, can effectively increase the passage of agents through the skin, offering significant improvement over current methods of drug delivery.

CONTACT: Michael Kaiser

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