Horizon Therapeutics’ (HZNP) competitor Selecta Biosciences (SELB) reported results phase 2 of SEL-212 (pegadricase plus ImmTOR) which failed to beat Krystexxa in refractory gout patients. SEL-212 achieved a numerically better response rate at 3 and 6 months, but the results failed to reach statistical significance. SEL-212 results confirm its prior efficacy profile which is only moderately better than Krystexxa monotherapy and it does not represent an apples-to-apples comparison as SEL-212 has an unfair advantage of the addition of ImmTOR, Selecta’s immunomodulator, to pegadricase, which is the biologic candidate with the same mechanism of action as Krystexxa (pegloticase).

I believe SEL-212’s phase 2 results further solidify Krystexxa’s likely leading position in the refractory gout market given the emerging and very strong combination data of Krystexxa with approved immunomodulators (mainly methotrexate). I expect the combination to achieve much greater efficacy in the ongoing MIRROR study than SEL-212 will in its phase 3