- Roche's Hemlibra wowed Wall Street yet again on Monday, as fresh data from the late-stage HAVEN program showed the drug is a powerful prophylaxis treatment for hemophilia A patients with and without inhibitors.
- The HAVEN 3 trial enrolled patients 12 years and older with Factor VIII inhibitors, and found those who received prophylactic Hemlibra every week experienced a 96% reduction in treated bleeds, compared to those who didn't get preventative treatment. The trial also evaluated Roche's drug at two-week intervals. Patients in that arm demonstrated a 97% reduction in treated bleeds versus the no-prophylaxis arm.
- HAVEN 4, meanwhile, is a single-arm study that enrolled patients in the same age range with or without inhibitors. These patients received prophylactic Hemlibra every four weeks, resulting in 56% experiencing no treated bleeds per year and 90% experiencing three or fewer. Across the two HAVEN studies, there were no unexpected or serious adverse events related to Hemlibra treatment.
Analysts have predicted a major shake-up in the hemophilia market due to newer, longer-acting therapies like Hemlibra (emicizumab). It seems with each fresh slate of data, Roche gets closer to making those predictions a reality.
Hemlibra launched in November, and made CHF 23 million (about $23 million) during the first quarter. Investment bank Cowen & Co. expects the drug will hit CHF 2 billion by 2024, but acknowledged that's very conservative in a May 21 note — particularly in light of the new HAVEN results.
At a conference earlier this year, Cowen surveyed investors and key opinion leaders about Hemlibra. A majority of responders from both groups indicated that, to support use of the drug, HAVEN 3 would need to show more than 50% of patients who received Hemlibra had no treated bleeds. And in HAVEN 4, they said Hemlibra would need to show a median annualized bleed rate of no more than two bleeds.
In fact, HAVEN 3 found 55.6% of patients taking Hemlibra every week and 60% taking it every two weeks experienced zero treated bleeds. None of the patients in the no-prophylaxis arm were free of treated bleeds.
"The HAVEN 3 data appears to at least meet and possibly exceed expectations," Cowen analyst Steve Scala wrote in the note.
And in HAVEN 4, the median annualized bleed rate was zero.
The clean safety data were highlights as well, especially because regulators have expressed concerns about Hemlibra treatment and its potential blood-clotting effect. In March, Roche disclosed that five patients treated with its drug died, though investigators judged the cases unrelated to Hemlibra.
"Not seeing any of those safety signals in the non-inhibitor patients is somewhat reassuring," Michael Callaghan, assistant professor of pediatrics in the hematology and oncology department of Wayne State University School of Medicine, told BioPharma Dive.
What's more, the multiple doses tested between HAVEN 3 and HAVEN 4 bode well for patients switching to Hemlibra treatment.
"I think there will be a lot of patients who will would like to go to an infrequent [subcutaneous] injection if they're doing well, and then there are some patients where being adherent with multiple-times-a-week IV infusion has been hard, whether it's because they have poor IV access or just busy lives and difficulty with infusion," Callaghan said.
U.S. and European regulators have already approved Hemlibra for once-weekly routine prophylaxis of bleeding episodes in adult and pediatric hemophilia A patients with Factor VIII inhibitors. Roche announced in mid-April the Food and Drug Administration gave the drug breakthrough therapy designation for treating hemophilia A patients without inhibitors. Analysts expect an approval in that setting later this year.
With its current approvals, Hemlibra is poised to take big chunks out of inhibitor-focused therapies like Shire's Feiba and Novo Nordisk's NovoSeven. An OK in the non-inhibitor space would bring some disruption as well. Responses to Cowen's surveys, for instance, indicated that Hemlibra could secure 20-50% market share in the non-inhibitor market within three years of approval.