Bimatoprost 0.01% approved as first-line IOP therapy

The optimized reformulation with a reduced concentration of bimatoprost received FDA approval late August as a first-line therapy indicated for the reduction of elevated IOP in patients with open-angle glaucoma or ocular hypertension.

Bimatoprost's strength has been that it is highly potent in lowering IOP, but it has more of a side effect profile than other prostaglandin analogs (PGAs) approved in the United States for the treatment of glaucoma. The most common side effect of bimatoprost 0.03% has been hyperemia.

Switching to a lower concentration should achieve a comparable amount of pressure reduction but cause much less of the troublesome red eye, he added.

There has been no direct comparison of the two different concentrations. The new formulation was approved following a 3-month pivotal study of patients with open-angle glaucoma or ocular hypertension with an average baseline IOP of 23.5 mm Hg. The results showed that bimatoprost 0.01% lowered IOP up to 7 mm Hg from baseline.

Bimatoprost 0.01% has a similar overall safety profile, a favorable hyperemia profile, and less overall discontinuation compared with bimatoprost 0.03%, said Scott Whitcup, MD, Allergan's executive vice president, research and development, and chief scientific officer.

Although the new formulation of bimatoprost has a lower concentration of the active drug, it also has a higher concentration of benzalkonium chloride (BAK), 0.02% versus 0.005% in the original formulation. The BAK concentration in bimatoprost 0.01% is now the same as the BAK concentration found in latanoprost ophthalmic solution (Xalatan, Pfizer).