<prompt> Healthy volunteers are recruited in which phase of clinical trials?Phase 1Phase 2Phase 3Phase 4  <response>: Phase 1- Done on healthy people. Maximum tolerable dose of drug is tested Phase 2- Done on fewer patients 20-200 . Efficacy and safety of drug is tested here Phase 3-Done on more patients upto 5000.Efficacy is confirmed in this phase Phase 4- Post marketing surveillance. Long term and rare side effects are monitored in this phase 