Roche’s new spinal muscular atrophy offering Evrysdi is already attracting early interest thanks to its oral dosing, and the Swiss pharma hopes some longer-term data could further build its case for a three-way contest against Novartis and Biogen.
Evrysdi kept 88% of infants aged 2 to 7 months with symptomatic Type 1 SMA alive without permanent ventilation after two years, a new analysis of pivotal data found.
The infants also saw improvements in motor function. Compared with a previous study of one-year data, more patients were able to sit without support after two years of treatment, and more maintained upright head control, could turn themselves over or stand.
All infants increased their score on a test of motor skills, called CHOP-INTEND, from one year to two years. The data came from Part 1 of the pivotal Firefish study presented at the virtual International Annual Congress of the World Muscle Society.
Part 1 of Firefish started with a dose-finding phase, and patients will be followed for an additional three years in an open-label phase. Part 2 of the study finished enrollment in November 2018. Infants in that part got Evrysdi at the dose determined in Part 1 from the beginning and will also be followed for altogether five years.
Evrysdi hit the market last month, with eyes on Biogen’s blockbuster drug Spinraza and Novartis’ novel gene therapy Zolgensma.
As the first-to-market therapy, Spinraza already has five-year data; Biogen said in June that all presymptomatic SMA infants in the phase 2 Nurture study were still alive and none required permanent ventilation after up to 4.8 years of Spinraza treatment. Getting treatment before symptoms show up is considered a better situation for patients.
Evrysdi obviously doesn’t yet have such long-term data, but the Roche drug’s selling point lies in its oral dosing. In contrast, Spinraza is injected into the spinal cord every four months after the initial four, more frequent loading doses.
Spinraza’s intrathecal administration route has created some real-world challenges “which we believe will make families open to exploring other options like Evrysdi,” RBC Capital Markets analyst Brian Abrahams said in an investor note last week after talking to a caregiver and patient advocate who’s “highly involved in the SMA community.”
The caregiver described a “considerable administration burden,” in which her child needs to be pulled out of school for one month prior to Spinraza infusion to prevent any illness that would make the child unfit for the necessary anesthesia. Many hospitals don’t have anesthesia protocols in place, she said, making intrathecal administration even more difficult for some children.
In addition, her anecdotal reports suggest children taking daily Evrysdi have more “constant energy,” whereas Spinraza’s benefits appear to wane in between injections, “something we believe could prompt increasing interest in [Evrysdi],” Abrahams said.
Although Abrahams said he sensed the caregiver would be reluctant to switch therapy for her child as she has already worked through the logistical hurdles and is seeing significant treatment benefits in mobility and swallowing, she did note that these issues deter many patient families from starting with Spinraza.
There are families who are indeed interested in switching from Spinraza to Evrysdi, Roche's own statistics show.
Teresa Graham, Roche’s head of pharma global product strategy, said that about two-thirds of Evrysdi patients have prior experience with Spinraza or Zolgensma. Problem is, even at the caregiver's treatment center—which Abrahams describes as a major metropolitan academic hospital—Evrysdi’s not expected to be available for several months because of paperwork-related delays. This suggests Evrysdi’s third-quarter sales performance may not be as strong as expected, Abrahams predicted.
As for Zolgensma, families with younger Type 1 SMA children are “increasingly driven towards” the Novartis one-time gene therapy as a first-line treatment to avoid Spinraza’s injection routine. But there’s an emerging trend within the SMA community to pair these treatments in the hope that they may provide even better outcomes, the analyst said. Biogen has already planned the phase 4 Respond trial to test Spinraza in patients following Zolgensma.
“[T]his paints a picture of a more complementary, vs. competitive treatment landscape, and a caregiver view that double/triple combo therapy may be more beneficial than monotherapy,” Abrahams said, concluding that no one treatment may be able to dominate the SMA market.