The blue-chip NSE Nifty 50 index closed 0.1% lower at 11,504.95, while the benchmark S&P BSE Sensex, which has fewer pharma components, ended down 0.34% at 38,845.82.
The Nifty ended the week 0.4% higher, while the Sensex closed a tad lower.
The Nifty Bank Index finished 1.3% lower at its worst closing level in a month, capping its third straight week of losses, dragged by a 2.4% slide in top private-sector lender HDFC Bank.
The Nifty Pharma index clocked its best day since Aug. 10, closing up 5%, as drugmaker Dr.Reddy's Laboratories Ltd added 10.5% to close at a record high.
The pharmaceutical firm settled a patent litigation with U.S. drugmaker Bristol-Myers Squibb Co over the cancer treatment Revlimid, prompting analyst upgrades to its stock.
Drugmakers Lupin Ltd and Cipla Ltd jumped 4.7% and 7.3%, respectively, after U.S.-listed Perrigo Company Plc issued a U.S. nationwide recall of its albuterol sulfate inhalation aerosol product due to complaints of clogging issues.
Cipla and Lupin have their own versions of the aerosol product approved by the U.S. FDA.
Investor sentiment in broader markets was also tepid on worries over a resurgence in coronavirus cases and disappointment that central banks merely affirmed their monetary support this week, without promising new stimulus.
(Reporting by Anuron Kumar Mitra in Bengaluru; Editing by Ramakrishnan M.)