Congrats to Horizon Pharma (HZNP) and especially patients with thyroid eye disease (TED), on the positive phase 3 results reported yesterday for the use of their IGF-1 receptor inhibitory monoclonal antibody, Teprotumumab (Tepro), to treat this debilitating rare disease with no approved treatments currently. The phase 3 data, like the phase 2 data, showed a tremendous efficacy profile and good safety. Over 80% of patients on study drug vs. 9.5% of patients on placebo had a reduction of eye bulging (proptosis) of greater than or equal to 2 mm at 24 weeks (see graphic), which is a clinically meaningful change. This primary and all secondary endpoints were met with high statistical significance (p<=0.001). This drug should be life changing for these patients, many of whom suffer from social isolation during the active phase of the disease, and potentially eliminating the need for a series of difficult surgeries that are risky and provide mixed results.
Horizon has built quite a bit of momentum in the last few years in becoming an exciting rare disease company. First Krystexxa for gout and now Tepro for TED, demonstrate the effective corporate development function at this company to bring in high quality assets under reasonable terms. Investors, such as Amp, have been rewarded in the past year as Krystexxa sales have increased 65% and driven up HZNP's value. Now, with the over 30% market cap gain today from these excellent Tepro results, the company's value has almost doubled over the past year. Next for Tepro is a BLA filing with the FDA, which should have a very good chance of approval, followed by a 2020 commercial launch. The drug has orphan, fast-track and break-through therapy designations. In addition to patent protection, which we have not analyzed, if approved the company expects that Tepro will qualify for 12 years of biologic exclusivity, and estimates peak annual revenue in the U.S. at $750 million.