(Bloomberg) — A trial of NewLink Genetics Corp.’s experimental Ebola vaccine will resume in Geneva today, using a lower dosage to avoid the joint pain that led researchers to suspend tests last month.

The remaining 56 volunteers in the 115-person trial will receive 300,000 vaccine particles, compared with a dose of as many as 50 million particles that were given during the first part of the project, University Hospitals of Geneva said in a statement today. Final results are expected in March.

The vaccine “seems able to induce the production of antibodies at lower doses than those previously used,” according to the statement.

The Geneva trial is part of a race by drugs companies and public health officials to develop a vaccine against the viral infection that has infected more than 20,000 people and killed almost 8,000 in Sierra Leone, Liberia and Guinea. Tests are under way of a shot being developed by London-based GlaxoSmithKline Plc, while Johnson & Johnson plans to trial another vaccination.

NewLink shares were down 1.2 percent at $43.11 as of 9:41 a.m. in New York. The stock fell 4 percent on Dec. 11 when the Geneva hospitals suspended the trial after 10 volunteers reported mild-to-moderate joint pain 10 to 15 days after receiving the injection. The symptoms disappeared quickly without treatment, and none of the volunteers had to miss work or be hospitalized, according to today’s statement. Joint pain after infection or vaccination is common, according to the statement.

Merck & Co. Inc., based in Kenilworth, New Jersey, agreed in November to buy the rights to NewLink’s Ebola vaccine and work with the Ames, Iowa-based company to develop it.

See also:

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Ebola exposes coverage holes

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