<prompt> In which phase of clinical trials, post-marketing surveillance of a drug is carried outPhase IPhase IIPhase IIIPhase IV  <response>: Clinical trials divided into 4 phases Phase I: Human pharmacology and safety Phase II: Therapeutic exploration and dose ranging Phase III: Therapeutic confirmationcomparison Phase IV Postmarketing surveillancestudies-during this phase or after the release of the drug into the market, ADRs are monitored through pharmacovigilance centers. Ref ;KD Tripathi pharmacology 7 th edition page no; 80 