Alexion crowns myasthenia gravis as its best Soliris launch ever

At the very beginning of 2018, Alexion figured its new Soliris approval in generalized myasthenia gravis (gMG) could deliver its lead drug's best launch. Now, as its third-quarter numbers show, that expectation has become a reality.

First approved in 2007 to treat the rare blood disease paroxysmal nocturnal hemoglobinuria (PNH), Soliris earned the gMG nod last October. And by the end of September, 560 U.S. patients received the therapy, making it the best Soliris launch, executives said on the company’s third-quarter earnings call.

And that's a good thing for Alexion. Soliris is its sales engine, delivering by far the biggest numbers to its top line. In the third quarter, Soliris accounted for 86% of its sales, and followup drug could be more than a year away.

For the quarter, Soliris sales beat analysts' consensus and jumped 17.6% year-over-year to $888 million. Thanks to that strong growth, and now-formalized reimbursement agreements with the Turkish and Brazilian governments, Alexion is dialing up its revenue guidance by $40 million, to $4.02 billion to $4.05 billion.

If everything goes well, the muscle weakness indication could add $1.2 billion to Soliris’ 2022 sales, Leerink analyst Geoffrey Porges has said. Some other analysts have been less bullish because of pricing concerns.

Alexion is also looking to expand Soliris’ label to neuromyelitis optica spectrum disorder (NMOSD), another rare complement system-mediated disorder of the central nervous system with no approved therapies.

Just a month ago, in what executives painted as results that “far exceeded our expectations,” Alexion announced top-line data showing Soliris could cut the risk of NMOSD relapse by 94.2% compared to placebo. Because each relapse pushes NMOSD patients further toward disability and potentially premature death, the clear benefit led Porges to estimate $500 million to $700 million in additional revenue if the new indication wins approval. In a Wednesday note to investors, Porges said he expects that green light by the end of 2019.

RELATED: Alexion eyes $500M-plus in new Soliris sales with latest rare-disease win

The company now expects to put more money behind medical affairs and sales and marketing as it preps for potential launches, including expanding its sales footprint for Soliris in NMOSD, but also a brand-new drug, CFO Paul Clancy said on the Wednesday call.

That drug candidate is Ultomiris, also known as ALXN1210. The longer-acting version of Soliris recently demonstrated it works as well as its predecessor in PNH, and the FDA is scheduled to decide its fate by February 18 under a rare-disease priority review voucher. Competitors such as Roche/Chugai’s anti-IL-31 receptor antibody SKY59/RG6107 are far behind, and their clinical  profiles fall short of the Alexion drug's, Evercore ISI analysts previously noted.

Meanwhile, Strensiq, a treatment for the rare metabolic bone disease hypophosphatasia, hauled in $113.2 million for Q3, thanks to a 37% year-over-year volume increase. But that was a notable decline from the second quarter’s $125 million.

Management attributed the fall to the timing of orders outside the U.S. in the second quarter. “It’s an ultrarare disease, so there’s variability on both patient identification, and sometimes genetic testing is required, so there could be a lag effect of patients on-boarding to therapy,” Chief Commercial Officer Brian Goff explained on the call, adding that the team still feels good about the drug meeting its $500 million revenue expectation for the year.

RELATED: Alexion buys RNAi therapies in Dicerna deal

Alexion has also been mobilizing its M&A war chest recently, having snatched up Syntimmune along with its anti-FcRn antibody drugs, whose lead product has the potential to be first-to-market in warm autoimmune hemolytic anemia (WAIHA). It also just announced a deal with Dicerna that enables it to branch out into RNAi therapies. Moving forward, Clancy said the company will still press on with new deals, especially for clinical-stage assets.