New York, Aug 20 (AP) Pfizer and its German partner BioNTech will take its COVID-19 vaccine candidate with the fewest side effects into final-stage testing.

In an online report Thursday, Pfizer researchers compared data from early-stage testing of two vaccine candidates. Both revved immune systems similarly, and neither caused severe side effects.

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But one candidate caused considerably fewer injection reactions, particularly in older adults -- symptoms such as fever, headache, chills or muscle pain that are temporary but unpleasant, Pfizer reported.

Final testing of Pfizer's lead candidate has begun as researchers recruit about 30,000 people in the US and other countries. It's one of a handful of experimental vaccines to reach end-stage tests around the world.

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It generally takes years to develop a safe and effective vaccine for widespread use and distribution. US health officials hope to start offering vaccinations sometime next year. (AP)

(The above story is verified and authored by Press Trust of India (PTI) staff. PTI, India’s premier news agency, employs more than 400 journalists and 500 stringers to cover almost every district and small town in India.. The views appearing in the above post do not reflect the opinions of LatestLY)