An ongoing dialogue on HIV/AIDS, infectious diseases,
August 6th, 2017
Have We Reached the End of HCV Drug Development?
Two new HCV regimens gained FDA approval recently, bringing us closer to the end of this extraordinary phase of drug development.
Think about it — has there ever been a more spectacularly rapid improvement in treatment of anything? If so, please let me know what that is. Remember, as recently as early 2013, highly toxic interferon-based therapy (with ribavirin and telaprevir or boceprevir) was still standard-of-care.
The recent approvals: Sofosbuvir-velpatasvir-voxilaprevir (Vosevi) on July 18, indicated for patients who have failed prior treatment with either sofosbuvir or an NS5A inhibitor. Twelve weeks of treatment (one pill daily) will cure 95–96% of patients, and pretreatment presence of NS5A, NS3, or NS5B resistance mutations does not reduce response. A month of sof-vel-vox — which will only be used as a salvage therapy — is priced at $24,900.
Then, glecaprevir-pibrentasvir (Mavyret) was approved on August 3rd. A pan-genotypic regimen that includes both an HCV protease inhibitor and an NS5A inhibitor, “G/P” is 3 pills daily, requiring only 8 weeks of therapy in treatment-naive individuals without cirrhosis. Clinical trial results show cure rates in the high 90s, with a low incidence of treatment-related adverse events requiring drug cessation.
Glecaprevir-pibrentasvir can also be used in patients with renal impairment (including dialysis), prior treatment failure of genotype 1 with either an NS5A inhibitor or PI (but not both), and in compensated cirrhosis. Treatment duration should be increased to 12 weeks in those with prior treatment or cirrhosis.
So where does that leave us in terms of “unmet needs” in HCV therapy?
Let’s review what we currently have:
- Nearly 100% of those who get treated are cured.
- Most regimens are one pill daily.
- Ribavirin is rarely required for treatment-naive patients.
- Side effects leading to drug discontinuation are exceedingly uncommon.
- Treatment duration is only 8–12 weeks.
- Drug interactions are mostly manageable; if not, HCV treatment is so short that temporary discontinuation of the conflicting drug is usually fine.
- Several pan-genotypic options are available.
- Certain therapies are also effective for treatment-experienced patients with resistance.
- Some regimens are safe and effective for those with moderate-severe renal disease — even hemodialysis.
From a medical perspective, this doesn’t leave out a whole lot, does it? Treatment of HCV is so easy there’s a strong push in some circles to move it to front-line providers in primary care — and of course outcomes in their hands are as good as with hepatologists and ID specialists.
Yes, cost of and access to HCV therapy remains an issue, especially in certain regions.
But things have vastly improved in this area too. With prices way down from the crazy days of early 2014 (when the non-FDA approved “sim-sof” regimen was > $100,000/cure), we should anticipate that more payers will stop medically unjustified policies such as fibrosis criteria, negative toxicology screens, and limiting prescribing of HCV therapy to specialists.
And market forces are doing something — note that the wholesale price of G/P is $13,200 per month, very close to the negotiated discounted price for LDV/SOF with the VA and certain state Medicaid programs.
Which brings me back to the title of this post — Have We Reached the End of HCV Drug Development?
If we’re not there yet, we’re certainly close.
Here’s a poll about where we should go with HCV research — please vote!