2021 is drawing to a close, and Wall Street is ending the year with a whimper. Stock market indexes are modestly lower, with the Nasdaq Composite (^IXIC -0.64%) falling 0.2% as of noon ET.

As COVID-19 case counts have soared, investors have watched with interest to see the potential impact on companies that have fought hardest against the pandemic. Vaccine maker Moderna (MRNA -2.45%) picked up some ground on Friday, as investors anticipated that greater interest in COVID-19 vaccines and boosters could continue well into 2022. However, another stock in the biotech arena had much larger gains. Read on to find out more about it, as well as about Moderna's prospects going forward.

Researchers wearing lab apparel looking into microscopes.

Image source: Getty Images.

Moderna gets a variant boost

Shares of Moderna were up nearly 3% on Friday. The move comes as the omicron variant starts to take over from the previous delta variant and pushes case counts sharply higher.

The numbers have been increasingly ugly. Almost 1.9 million COVID-19 cases were reported worldwide on Thursday, including a record 572,000 cases in the U.S. alone. Counts in the U.K., France, Spain, and Italy were all over the 100,000 mark, and several other nations saw unprecedented numbers of cases as well.

It appears that regulators will seek to make current vaccines and boosters more readily available to the widest possible populations. For instance, a news report yesterday suggested that rival vaccine makers Pfizer (PFE -3.85%) and BioNTech (BNTX -1.57%) would be allowed to administer boosters on young teenagers, as well as look for ways to treat even younger children who have potential complications from autoimmune disorders.

As for Moderna, it still needs to have its mRNA-1273 vaccine fully approved by the U.S. Food and Drug Administration. Nevertheless, Emergency Use Authorization has been adequate to allow patients to receive the Moderna vaccine, and despite reluctance from large portions of the global population, the majority who've come around to the value of vaccines appear likely to keep turning to Moderna as the situation continues to develop.

A win for Cushing's syndrome sufferers

However, the big gain on the Nasdaq came from Xeris Biopharma (XERS), which saw its shares soar 27%. The small Chicago-based biopharmaceutical company announced success in its quest to provide a treatment for those suffering from a rare disease.

Xeris announced that the FDA had approved the use of Recorlev for treating endogenous hypercortisolemia in adult patients suffering from Cushing's syndrome. The treatment provides an alternative for those who either cannot be treated for surgery or for whom surgical procedures haven't produced a cure to the disease. Late-stage clinical trials had shown that Recorlev significantly reduced cortisol concentrations and kept that at normalized levels while meeting safety standards.

Going forward, Xeris hopes to make Recorlev available to patients in the first quarter of 2022. CEO Paul Edick was understandably pleased with the news, and he argued that it helped to justify the strategic move Xeris made recently to acquire industry peer Strongbridge Biopharma and its pipeline of rare disease treatments back in October.

Even with the rise, though, Xeris still trades far below its best levels from shortly after its 2018 IPO. It'll likely take more success stories similar to Recorlev's in order for Xeris to regain the full confidence of long-term shareholders in the biotech company's stock.