Summit slips as Leerink doubts cancer drug can match Keytruda's success

Shares of drug developer Summit Therapeutics SMMT.O fall 3.6% to $21.28 premarket

Brokerage Leerink Partners starts coverage on SMMT with "underperform" rating and $12 PT, a 46% downside to the stock's last close

Brokerage says it doesn't believe SMMT's lung cancer therapy, ivonescimab, is "the next Keytruda", Merck's MRK.N blockbuster cancer drug

Views SMMT as "by far the worst-positioned" competitor, requiring a major partnership beyond their Pfizer PFE.N ADC collaboration to compete effectively

Leerink believes SMMT's drug faces "unrealistic share" expectations in the cancer immunotherapy market, given the "intense and heterogeneous competitive landscape"

Summit faces "unfavorable cost dynamics" including "low-double-digit royalties" to Chinese partner Akeso 9926.HK and reliance on contract manufacturers - brokerage

As of last close, stock up 23.7% YTD