FRANKFURT, Nov 3 (Reuters) - Germany's BioNTech on Monday lifted its 2025 revenue guidance after receiving initial payments from its new partner Bristol Myers Squibb in a cancer immunotherapy alliance that seeks to challenge Merck's best-selling Keytruda.

US-listed shares of BioNTech gianed 2% in premarket trading.

BioNTech, Pfizer's partner on COVID-19 vaccines, said it was projecting full-year revenue of 2.6 billion euros ($3.03 billion) to 2.8 billion euros, up from a previous guidance range of 1.7 billion to 2.2 billion euros.

Earlier this year, Bristol agreed to pay up to $11.1 billion in the partnership deal over time, depending on achievements.

BioNTech said on Monday that the partners extended their clinical trial programme for the cancer drug in question, pumitamig, during the third quarter and would add more trials by next year.

The German biotech firm said third-quarter revenue gained 22% to 1.52 billion euros.

BioNTech is pivoting its focus to cancer drugs, which are expected to drive future growth of the company, as revenue from its COVID-19 vaccine steadily decline from their pandemic era highs.

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