Dec 19 (Reuters) - The U.S. Food and Drug Administration has approved Cytokinetics' oral drug to treat a rare heart ‌condition, the company said on Friday.

The keenly watched drug, branded as Myqorzo, was approved for patients with obstructive hypertrophic cardiomyopathy, a ⁠condition in which the heart muscle becomes abnormally thick, limiting the heart's pumping and causing symptoms such ‌as shortness of breath, chest pain and dizziness.

About one in every 500 people in the United States suffers from hypertrophic cardiomyopathy, with a large portion having the obstructive variant.

Myqorzo marks Cytokinetics' first FDA-approved product and only the second drug of its class to win U.S. clearance, offering a treatment that addresses the underlying disease.

The company ⁠said Myqorzo is expected to be available in the U.S. in the second ​half of ⁠January and will come with the regulator's most serious warning for the risk of heart failure.

It would be available only through a risk evaluation and mitigation ‌strategy (REMS), a safety program to protect patients from risky drugs, ‌the company said.

Myqorzo is ​a cardiac myosin inhibitor, the same ‌class as Bristol Myers Squibb's Camzyos, which was approved in 2022 for the condition and carries a similar warning for the risk of heart failure.

Myqorzo seems safer and easier to use compared to Camzyos, Mizuho analyst Salim Syed ​said, adding that convenience factor would be key, especially for ​previously ⁠CMI-naive patients and physicians.

Cytokinetics said it will announce the drug's list price before it becomes available in January. It expects Myqorzo ‍to be priced in line with Camzyos.

Myqorzo, chemically known as aficamten, reduces the forceful heart muscle contractions and has shown to be more effective compared to standard-of-care blood ‌pressure drug metoprolol in studies.

In late-stage trials aficamten improved exercise capacity and ​reduced symptoms in patients with the condition.

(Reporting by Kamal Choudhury and Mariam Sunny in Bengaluru; Editing by Shinjini Ganguli and Alan Barona)