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Feb 26 (Reuters) - The U.S. Food and Drug Administration on Thursday approved Boehringer Ingelheim's zongertinib as a first-line treatment for a rare form of non-small cell lung cancer, making it the second drug cleared under the agency's new speedy review program.

Zongertinib, to be sold under the brand name Hernexeos, is approved for patients with non-small cell lung cancer whose tumors carry a rare genetic mutation and who have not received prior therapy.

The mutation occurs in about 3% to 5% of such cases.

The approval expands Boehringer's presence in the market for targeted lung cancer therapies, where it will compete with other treatments, including Bayer's BAYGn.DE Hyrnuo.

Zongertinib is among 18 drugs the agency has selected so far for the FDA Commissioner's National Priority Voucher Program, which aims to cut review times to one to two months from the typical 10 to 12 months.

The program, launched in June, is designed to speed decisions on select drugs deemed critical to public health or national security, or that are manufactured in the United States or offered at low prices.