The European Medicines Agency recommends suspending the sale of hundreds of drugs that were authorized for use across the continent based on “flawed” clinical studies that were conducted by GVK Biosciences, a clinical research organization based in Hyderabad, India.

The regulator decision follows an inspection last May by French regulators that raised concerns about the reliability of several studies conducted at the site between 2008 and 2014 on behalf of various drug makers. The inspection found anomalies in the way that...