Shares of WW International Inc jumped 40% to a one-month high Tuesday after Goldman Sachs upgraded the stock to "buy," expecting the weight-loss services company's entry into the obesity drug business to help drive a turnaround.

Goldman lifted its target price on the stock to $13 — the highest on Wall Street — from $3.80, according to Refinitiv data.

The new target price implies the stock will more than triple in the next 12 months. Median price target for the New York-based company is $4.50.

The stock was last trading at $5.80.

The subscriber base and earnings power of the company, also known as WeightWatchers, have been shrinking, but a catalyst for a turnaround has emerged with the new obesity drug solution, Goldman analyst Jason English wrote in note.

WeightWatchers, which offers weight loss and weight management programs, entered the obesity drug prescription business last month with its acquisition of telehealth platform Sequence. The deal news sent its shares 79% higher on March 7.

Subscription company Sequence through its clinicians can prescribe medications such as Novo Nordisk's Wegovy and Saxenda — currently approved drugs for obesity in the United States.

Analysts have forecast the global obesity market to be worth around $50 billion in sales in 2030.

The latest acquisition could help WeightWatchers revive its top line as it continues to lose subscribers at its legacy business.

The company's revenue dropped 18% to $223.9 million in the fourth quarter from a year earlier.