Astellas Pharma is seeking approval for eye treatment Izervay in Japan and Europe, a bid to expand sales to counter a potential revenue drop for its top cancer medicine.

The drugmaker is in discussions with Japanese regulators about whether clinical trials for local patients are needed, Chief Executive Naoki Okamura said. If they aren’t, the Tokyo-based firm plans to file for a greenlight "as soon as possible,” he said.

Astellas has already filed for approval in Europe, he added.

The drug treats age-related macular degeneration and was developed by Iveric Bio, which was acquired by Astellas. U.S. regulators approved Izervay last year, and sales of ¥12.1 billion ($77 million) for the fiscal year ending in March were "better than expected,” Okamura said.

Izervay is one of several new medicines Astellas is counting on to make up for a potential drop in sales when its biggest-selling cancer drug, Xtandi, faces generic competition in the U.S. from 2027. The company is also banking on fezolinetant, sold in the U.S. under the brand name Veozah, which treats hot flashes in menopausal women. Astellas will be focused on raising awareness of fezolinetant among doctors while expanding insurance coverage for the drug, Okamura said.

The firm will continue to make small early-stage investments but has ruled out "large-scale” mergers and acquisitions in the next few years, he added.