Perhaps coming as a surprise, particularly given Otezla’s strong performance to date in grabbing market share in the psoriasis space (the drug is expected to generate $1.5 billion in sales in 2017), an extensive review of Otezla's published clinical findings showed that Celgene’s blockbuster did not statistically outperform methotextrate in the treatment of moderate-to-severe cases.
The researchers calculated the difference-in-difference in PASI 75 response rates between apremilast vs. placebo in the ESTEEM trials and methotrexate vs. placebo in the CHAMPION trial. PASI 75 was achieved after 16 weeks by 36.6% of patients taking apremilast and 36.4% of patients taking methotrexate, while placebo treatment had response rates of 18.9% and 6% in the CHAMPION and pooled ESTEEM trials, respectively.
While it’s too early to know if such findings might ultimately impact Otezla sales, given its parity as to efficacy with the much less expensive methotextrate, what the study does reinforce is physician and patient receptivity to oral psoriasis therapies, even moderately beneficial ones.
Prurisol has similar potential, reflecting the rising value of oral therapies in treating psoriasis. The drug already has performed comparably to Otezla when it was at a similar stage of development. In the current clinical trial, a Phase 2b assessing moderate-to-severe psoriasis, Prurisol might show even greater efficacy after an evaluation of higher dosing regimens, 300mg and 400mg respectively.
““Among systemic-naïve patients with moderate-to-severe psoriasis, there were no statistically significant differences between apremilast and methotrexate. In addition, the [incremental cost per responder] with apremilast vs. methotrexate is high. … These results could provide clinically and economically relevant implications for health care decision makers.”