After a successful Phase III trial, Bristol-Myers Squibb’s Camzyos (mavacamten) has received US Food and Drug Administration (FDA) approval for use in obstructive hypertrophic cardiomyopathy (HCM) patients. Camzyos, a first-in-class allosteric modulator, is a myosin inhibitor that acts by blocking the function of the myosin motor protein central to smooth muscle contraction. This mechanism of action targets the disease’s underlying pathophysiology more specifically than existing therapies, such as angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers (ARBs), which are generic and used for a wide range of cardiovascular diseases. In addition to being first-in-class, Camzyos is also the first drug to ever be developed for obstructive hypertrophic cardiomyopathy. These attributes provide a favourable marketing position for Camzyos, which GlobalData expects to generate nearly $1bn in sales worldwide by the year 2025.
Cardiomyopathy is a cardiovascular condition that affects the heart’s ability to pump blood. HCM is one of four subtypes of the indication and is characterised by abnormally thick heart muscle. Obstructive HCM occurs when there is a blockage in the heart preventing blood outflow. Before Camzyos, there had not been medications indicated for obstructive HCM and the disease was either managed with generic cardiovascular therapies or surgical interventions such as surgical ablation, surgical resection of part of the ventricle, or alcohol ablation. Now obstructive HCM patients can be prescribed Camzyos with a starting dose of 5mg once daily with subsequent doses with titration at 2.5mg, 5mg 10mg or 15mg once daily. When asked about the potential for Camzyos to have widespread market penetration, an EU-based GlobalData key opinion leader said:
“[The proportion of patients who will be treated with mavacamten in five years] depends entirely on the pricing and local policies. For example, in [country redacted] and most of Europe…because of national health system restrictions, I would expect the drug to be less expensive than in the US because of course the government impacts heavily on the pricing… And therefore, there would be restrictions for patients that meet the inclusion criteria for the Phase III trial, which means that probably, given 100 patients that I see in my clinic with obstruction, that would probably make up to 25% to 30%. Possibly a little more, maybe up to 40%. If the drug came, ideally, at a much lower price and with no restriction, I would be inclined to give it to the vast majority of patients with obstruction…I think the drug has incredible actions on the myocardium and potentially modifies the disease.”
– EU Key Opinion Leader
Despite the success Camzyos exhibited in clinical trials, the drug will likely not displace any current therapy options given its cost, as well as the fact that the drug can be administered in tandem with drugs like beta blockers.
“When mavacamten comes out, people will stay on what they’re on and just have mavacamten added. That’s not really an issue because beta blockers and verapamil are generic drugs; they’re very inexpensive. And patients who are on them are tolerating them. So it’s not an issue of having to stop something or make a choice between two drugs.”
– US Key Opinion Leader
“Mavacamten will probably be used as a supplement in the studies. I don’t think they stopped the standard therapies…[Participants] could be on a beta blocker…They were allowed to continue beta blockers and calcium channel blockers. So, the study that so far has been the main study…showed in obstructive HCM, the benefits were on top of standard therapy, with the exception of disopyramide, which is the lesser used of the three drugs.”
– US Key Opinion Leader
With Camzyos launched in the US this year, European Medicines Agency (EMA) approval will follow soon afterwards as Phase III trials are ongoing throughout Europe. With strong commercial and clinical profiles, Camzyos will find success as it currently enjoys a free market. The drug will, however, eventually face competition with the market launch of Cytokinetics’ aficamten, another myosin inhibitor that also targets obstructive HCM.