Abstract

Concern has been raised about whether HPV vaccines might cause serious neurological disorders including postural orthostatic tachycardia syndrome (POTS) and chronic regional pain syndrome (CRPS). The European Medicines Agency (EMA) investigated the issue and declared in 2015 that there is no link between HPV vaccines and serious neurological adverse events. However, the certainty conveyed in EMA’s official report is undermined by a leaked, confidential document that reveals important disagreements among the experts. Furthermore, in its assessments, EMA relied on the data the drug companies had provided to them even though it had been demonstrated that the companies had underreported possible neurological harms. Even though active comparators were used (aluminium adjuvants and other vaccines), our research group found significantly more serious neurological harms in the HPV vaccine groups than in the comparator groups in a systematic review based on clinical study reports in EMA’s possession. We outline areas where we believe the basis for EMA’s decision was flawed; highlight that the relationship between HPV vaccines and POTS remains uncertain; and suggest ways forward to resolve the uncertainty and debate.