By Nikolaj Skydsgaard

Danish drugmaker Lundbeck beat first-quarter sales expectations on Tuesday as distributors and patients stocked up on medicines amid lockdowns to contain the coronavirus pandemic.

The company also said the U.S. launch of recently-acquired migraine drug eptinezumab, branded as Vyepti in the United States, had largely been a success, despite lockdowns forcing sales teams to switch from meetings with doctors to online contact.

"In a launch perspective, we've largely been as effective. But obviously, what hampers sales is that some hospitals and clinics have restrictions on letting patients in," chief financial officer Anders Goetzsche told Reuters.

Lundbeck, which specialises in treating mental disorders, joined rivals including AstraZeneca, GlaxoSmithKline and Novo Nordisk in benefitting from stockpiling of drugs as restrictions on movement were introduced across the world to tackle the coronavirus outbreak.

"Demand has been strong, but we also recognize that we have benefitted from patients gaining longer refill prescriptions as well as some stocking of products in many countries in response to the COVID-19 pandemic," Chief Executive Deborah Dunsire said in a statement.

The Copenhagen-based company posted quarterly sales of 4.56 billion Danish crowns (536.48 million pounds), above an average forecast of 4.34 billion in a Refinitiv Eikon poll of analysts, and an 8% increase from the same period last year.

Despite the strong first quarter, however, Lundbeck said it would maintain its full-year forecasts, with Goetzsche saying he expected sales would be affected by an unwinding of stockpiles in the second and third quarters.

Lundbeck shares topped the Copenhagen blue chip index in early morning trade, but were down 0.56% at 1036 GMT.

Sydbank analyst Soeren Loentoft Hansen linked the decline to the likely reversal of the stockpiling and to uncertainty over Vyepti's rate of take up in the United States.

Vyepti is the first migraine treatment of its kind, administered intravenously once every third month.

Lundbeck hopes it will eventually generate more than $1 billion in sales per year, but it will compete in a lucrative market with injectable treatments developed by rivals Eli Lilly, Amgen Inc and Teva.

The first patient was treated with Vyepti on April 6 and Goetzsche said negotiations with insurance planners were going as expected, adding several infusion centres and migraine experts had already bought Vyepti to treat patients.

Lundbeck expects to submit eptinezumab for regulatory approval in the European Union during 2020, and later in China and Japan.

(Reporting by Nikolaj Skydsgaard; Editing by Louise Heavens and Mark Potter)