UPDATE 2-Japan's Takeda to buy Nimbus' psoriasis drug for as much as $6 bln

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Dec 13 (Reuters) - Takeda Pharmaceutical will buy U.S.-based Nimbus Therapeutics' experimental psoriasis drug for up to $6 billion, the Japanese drugmaker said on Tuesday, as it looks to cut reliance on treatments facing loss of patents.

The drug, codenamed "NDI-034858", last week showed statistically significant reduction in moderate-to-severe psoriasis in a mid-stage study and is expected to enter late-stage trials next year.

The company is also studying the drug to treat inflammatory bowel disease and psoriatic arthritis.

The deal involves an upfront payment of $4 billion and an additional $2 billion if the drug achieves certain sales-based milestones, the companies said.

The upfront payment will be primarily funded by cash on hand.

Takeda's mainstay treatments such as ulcerative colitis drug Entyvio stare at intensifying competition in the next few years as they lose patent protections.

Earlier this month, the company's dengue vaccine was authorized for use in the European Union and Takeda had beefed up its portfolio through a $62 billion deal for Shire in 2019. (Reporting by Khushi Mandowara Editing by Vinay Dwivedi and Sriraj Kalluvila)