Tema ETFs has launched a new exchange traded fund that tracks popular drugmakers like Novo Nordisk and Eli Lilly, aiming to tap into growing demand for their weight-loss and diabetes drugs.

Successful drugs from Novo Nordisk and Eli Lilly are just the beginning of what one analyst says could be “the largest therapeutic class of drugs that the biopharma industry has ever seen.”

Retail flows into Eli Lilly spiked to a more than two-year high in November, as small investors rushed to buy the stock after the U.S. pharma major received a highly anticipated approval for its weight-loss drug Zepbound.

To help cope with the high demand for weight-loss treatments, Eli Lilly is reportedly investing $2.17 billion in a German manufacturing facility after last week’s FDA approval of Zepbound for chronic weight management.

Just a week after it secured FDA approval, Eli Lilly’s Zepbound now faces a challenge from Novo Nordisk’s investigational next-generation weight-loss candidate CagriSema in a Phase III trial.

The project will be fully funded by the medicines giant, which has seen surging demand for its diabetes drug Mounjaro, now also being used off-label for weight loss, according to sources familiar with the matter.

Eli Lilly on Thursday said it has not yet gained approval in Britain for the injection pen it plans to use for its Mounjaro drug against obesity and diabetes, adding to uncertainty over timing of the product’s launch.

U.S. companies across sectors such as food and beverage makers and manufacturers of glucose monitors have faced investor questions over the risk to future sales from the growing popularity of promising weight-loss treatments.

As the COVID-19 pandemic continues to recede, the top pharma companies intensified their focus into areas such as cancer and metabolic diseases to build up their pipelines, and their growth prospects, for the future.