NEW YORK (Good Medical) – Catalyst Pharmaceuticals Inc. announced Monday that its drug for the treatment of a rare condition, available for free for a long time to patients, would cost more than $ 300,000 a year, given to insurers and other discounts included .

The drug, Firdapse, is used to treat Lambert-Eaton Myasthenic Syndrome (LEMS), a rare neuromuscular disease.

US Senator Bernie Sanders sent a letter to Catalyst last week asking the company to justify its prices.

For years, patients had been able to get the drug for free from Jacobus Pharmaceuticals, a small New Jersey-based pharmaceutical company that offered it through the US Food and Drug Administration's "Compassionate Use" program. The program allows people with rare diseases to access experimental drugs outside of a clinical trial if there is no viable alternative.

Florida-based Catalyst, which received US approval for the sale of the drug in November, has set a list price of $ 375,000 a year.

In a presentation to investors at a conference in New York Monday, Catalyst said it expects the net price to be between $ 300,000 and $ 318,750 a year, which means that rebates and other discounts will reduce costs by 15 to 20%.

In the United States, drug manufacturers set a list price for their products, but generally offer discounts and after-sales discounts to encourage insurers and drug benefit managers to pay for drugs. Last month, the Trump administration proposed a rule to end the sector rebate system, which is undergoing a thorough review.

The drug Catalyst has also been granted orphan drug status by the FDA, which has a seven-year marketing exclusivity to encourage the development of drugs for rare diseases. The agency grants orphan status to drugs that treat diseases or affect fewer than 200,000 people in the United States.

Catalyst purchased Firdapse's rights from BioMarin Pharmaceuticals in 2012.

The Drug Benefit Manager, Express Scripts, a unit of insurer Cigna Corp, has stated that Firdapse is a covered drug on its form for the small number of patients meeting its coverage criteria.

But a spokeswoman for Express Scripts said that pricing "takes advantage of vulnerable patients who need this drug" and has described Catalyst as an example of misuse of the Orphan Drug Law Act.

Catalyst General Manager Patrick McEnany declined to comment except to say that the company would respond to Senator Sanders' request as soon as possible.

Report by Michael Erman and Caroline Humer; edited by Bill Berkrot