So far, so good for Alexion's Soliris follow-on
- Alexion Pharmaceuticals aims to convert more than 70% of paroxysmal nocturnal hemoglobinuria (PNH) patients taking its drug Soliris to a follow-on, Ultomiris, within two years of the newer treatment's launch. So far, Ultomiris is off to a good start in achieving such a goal.
- The biotech said during a meeting with investment bank Leerink and confirmed to BioPharma Dive that 13% of U.S. PNH patients on Soliris are in the company's OneSource support program for conversion to Ultomiris. Alexion said 8% have begun treatment with the drug.
- That percentage is up from the end of January, when about 5% of Soliris PNH patients had been confirmed as OneSource cases for potential conversion and around 2.5% had initiated Ultomiris therapy. The quick growth "suggests Alexion is tracking well to their guidance here just two months into the launch," Leerink analyst Geoffrey Porges wrote in an investor note.
Soliris (eculizumab) is a blockbuster therapy that works by inhibiting the complement system, a part of the body's immune response. It's also responsible for the vast majority of Alexion's revenue.
Though the drug's composition of matter patents should hold in the U.S. and Japan until the mid- to late-2020s, the story is a bit different in Europe, a market which accounts for roughly 25% of Soliris sales. There, the composition of matter patent runs out in 2020, opening the door to copycat treatments.
Leerink doesn't expect biosimilar versions of the drug in Europe until at least 2022. But having Ultomiris (ravulizumab) in its arsenal offers a safeguard to Alexion's complement business. (Ultomiris is currently under review for approval by European regulators.)
Such succession planning is a common — and at times, controversial — practice in the biopharma industry, as companies work to stave off the negative effects of patent expiries and lapsed monopoly positions.
The biotech gave Leerink more details of the follow-on's launch, like how the bulk of patients starting Ultomiris treatment are those who were switching from Soliris.
"Many of the conversions right now are occurring in patients who live further away from infusion centers and have the greatest commute burden with every 2-week Soliris dosing," Porges noted." Alexion also indicated that many of the physicians who have switched patients are not in the tertiary academic centers since these institutions often have formulary determinations for treatment and have not yet adopted Ultomiris."
Alexion estimates combined Soliris and Ultomiris sales will be around $4 billion for 2019. The company also told Leerink it expects 10% of its business to be at risk to initial biosimilar competition in 2022 to 2023, a lower figure than what the investment bank had forecast.
Soliris holds three indications: for PNH, atypical hemolytic uremic syndrome and generalized myasthenia gravis (gMG). The latter indication is the most recent, with a Food and Drug Administration approval in October 2017.
Leerink said Alexion execs have made the Soliris launch in gMG a priority. Though the company said it doesn't break down revenue by indication, it wrote in an email to BioPharma Dive that there were 788 patients with gMG on Soliris in the U.S. at the end of 2018.
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