Sofpironium bromide is a proprietary new chemical entity that we are currently developing in the U.S. as a potential best-in-class, self-administered, once-daily, topical therapy for the treatment of primary axillary (underarm) hyperhidrosis. We are on track to initiate the pivotal Phase 3 program in the U.S. for sofpironium bromide gel, 15% during the fourth quarter of 2020, which will ultimately be comprised of two pivotal Phase 3 trials to evaluate sofpironium bromide gel compared to vehicle (placebo) in approximately 350 subjects (per trial) with primary axillary hyperhidrosis.
In addition, on September 25, 2020 we announced that our development partner, Kaken Pharmaceutical Co., Ltd., received regulatory approval to manufacture and market sofpironium bromide gel, 5% under the brand name ECCLOCK® in Japan for the treatment of primary axillary hyperhidrosis.
Sofpironium bromide was designed as a structural analog of a well-known potent anticholinergic, glycopyrrolate, to achieve its therapeutic effect at the application site (skin) similar to glycopyrrolate. However, it differs from glycopyrrolate in that sofpironium bromide was retrometabolically designed. Retrometabolic drugs are intended to exert their action topically and are potentially more rapidly metabolized once absorbed into the blood. This retrometabolic approach to drug design is intended to allow for highly effective doses to be used while limiting systemic side effects.
Key design attributes of a retrometabolic drug include:
- The synthesis of a retrometabolic drug is achieved by starting with a known inactive metabolite of a known active drug (e.g., glycopyrrolate).
- The inactive, or less active, metabolite is then structurally modified to an active form (an analogue of active drug in this case; glycopyrrolate) that will undergo a predictable one-step transformation back into the inactive metabolite in vivo.
- Thus, the retrometabolic drug concept is based upon predictable metabolic deactivation processes by enzymes found predominantly in the systemic circulation.
Sofpironium bromide is delivered as a gel formulation in a metered-dose pump with an applicator that allows patients to avoid unwanted direct contact to the hands or other non-axillary body parts. We believe that this will help avoid certain side effects that could be caused by the unintended transference of the drug such as to the eyes.