The stock market has been on a solid upward trajectory recently, and the Nasdaq Composite (^IXIC 0.43%) has largely been leading the way. With so many stocks in high-growth areas like technology, the Nasdaq has been at the center of key trends driving stocks back higher after 2022's bear market. Monday morning brought a brief pause to the rally, but futures on the Nasdaq were still up slightly in the early morning session.

A couple of biotech stocks stood out as big winners in the Nasdaq on Monday morning. Both Argenx (ARGX -0.13%) and BridgeBio Pharma (BBIO -1.08%) moved sharply higher, as both companies had good news to announce that inspired shareholders to be more optimistic about what the future will bring.

Argenx gets encouraging trial results

Shares of Argenx were 27% higher in premarket trading on Monday morning. The Dutch biotech company announced favorable results in a key clinical trial, and investors were pleased with the implications for the company's future.

Argenx has been conducting a study evaluating its Vyvgart Hytrulo candidate treatment for adult patients suffering from the autoimmune disease chronic inflammatory demyelinating polyneuropathy (CIDP). The study's primary endpoint was reducing the risk of CIDP relapse among patients, and Vyvgart Hytrulo met that endpoint, showing a greater than 60% reduction in relapse rates compared to a placebo. In addition, the study showed that two-thirds of patients showed evidence of clinical improvement, which was a proof of concept for Argenx that demonstrated that a set of autoantibodies play a significant role in the biology of the disease.

The news comes less than a month after Argenx won U.S. Food and Drug Administration approval for Vyvgart Hytrulo in treating myasthenia gravis. The treatment became the first subcutaneous injection for treating the muscle disease, and Argenx expected U.S. patients to gain access sometime this month.

Overall, Argenx has a lot of good things going on, including a possible treatment for a condition linked to post-COVID patients. Shareholders seem particularly excited that Vyvgart Hytrulo could treat patients with a wide range of indications, and that could help bolster long-term sales for the biotech as it hits its stride.

Building a Bridge over troubled waters for rare heart disease patients

Shares of BridgeBio Pharma soared even further, climbing 53% in premarket trading. Phase 3 trial results were the motivating factor for the move higher, as BridgeBio is seeing encouraging levels of effectiveness for an important candidate treatment.

BridgeBio has been conducting a late-stage trial of its investigational small molecule stabilizer acoramidis and its impact on patients with transthyretin amyloid cardiomyopathy (ATTR-CM). The study met its primary endpoint, which was a combined metric considering mortality levels, frequency of hospitalizations for cardiovascular conditions, and changes from baseline in six-minute walking distance and another disease-specific metric. Improved survival rates approached actuarial models for life expectancy for people not suffering from ATTR-CM, which was another important accomplishment.

Because of the favorable results, BridgeBio now intends to submit marketing applications for acoramidis to the FDA before the end of the year. It will follow up with requests for regulatory approval in other countries early in 2024.

The news is especially good for BridgeBio because a previous clinical trial hadn't produced positive results. The follow-up data restored investor confidence in the company, and it'll now be interesting to see what the FDA will say when it considers BridgeBio's application over the next year or so.