Leerink analyst David Larsen says he's more cautious on Express Scripts (ESRX) after a redacted version of Anthem's (ANTM) lawsuit against the company became accessible yesterday. The analyst finds it increasingly likely that Anthem and Cigna (CI), should their merger go through, will bring in-house their Pharmacy Benefits Management. Express Scripts and some shareholders are underestimating Anthem's desire and willingness to walk away from the contract, Larsen tells investors in a research note. He thinks the relationship between the two companies has deteriorated to a point where the most likely outcome is termination of the contract either before or at the 2019 end-date. Further, Larsen believes that if Anthem and Cigna bring the contract in-house, shares of Express Scripts could trade to $50. Walgreens Boots Alliance could "aggressively pursue" an acquisition of the company under such a scenario, the analyst contends. He lowered his price target for Express Scripts to $65 from $80 and keeps a Market Perform rating on the shares. The Pharmacy Benefits Manager closed yesterday down 3% to $67.52.