Deutsche Bank has upgraded Merck (MRK) to a 'Buy' rating, expressing optimism about the company's future beyond the patent expiration of its key drug, Keytruda.

Merck is restructuring its business by separating its oncology division from non-cancer drug operations, a move reportedly in preparation for the 2028 patent expiry of its blockbuster cancer treatment, Keytruda.

Merck & Co. saw its stock advance, driven by robust sales of its drug Keytruda and favorable results from recent clinical trials.

Merck announced plans to divide its human health business into two separate divisions, separating its cancer franchise from non-oncology medicines, to mitigate the impact of Keytruda patent loss.