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By Bhanvi Satija and Christy Santhosh

June 11 (Reuters) - Britain's medicines regulator approved Novo Nordisk's NOVOb.CO weight-loss pill on Thursday, giving patients a new needle-free treatment option and bolstering the Danish drugmaker's first-to-market lead against U.S. rival Eli Lilly LLY.N.

The approval gives more than 10 million people living in England a more convenient alternative as drugmakers race to expand use of the medicines, which have transformed demand for weight-loss treatments and reshaped the pharmaceutical industry.

UK's Medicines and Healthcare products Regulatory Agency approved the pill for adults with obesity who have a body mass index of 30 or above, or those with a BMI between 27 and 30 and at least one related condition.

U.S.-listed shares of Novo rose 2% in morning trading.

Novo also received an early approval in the U.S. for its weight-loss pill and a launch earlier this year, while Lilly moved quickly behind, rolling out its oral medication, Foundayo, after getting a regulatory go-ahead in April.

Both drugmakers are aiming to increase their share of the rapidly growing obesity drug market, which analysts expect to surpass $100 billion annually in the next decade, by expanding into oral treatments.

"Oral GLP-1s will bring more people into treatment and give patients greater choice, but they are not silver bullets," said Danielle Brightman, clinical director at UK-based private digital healthcare platform Numan.

The pill contains semaglutide, the same active ingredient used in Novo's blockbuster injectable drugs Wegovy for weight loss and Ozempic for diabetes.

The approval will be followed by an assessment by Britain's National Institute for Health and Care Excellence before the pill becomes available on NHS.

Until then, patients can access the pill through private providers. Novo expects the drug to be available through private channels within weeks.

Obesity affects about 30% of adults in England, equivalent to an estimated 13 million to 14 million people, according to latest estimates by NHS England.