The main stock indexes are way down over the past year, but quite a few under-the-radar stocks have bucked the trend. All three of the stocks on this list are up near 52-week highs.

Despite an already eye-popping performance, there's a chance these stocks could climb even higher. Here's what to look out for in the months ahead from these high flyers.

Reata Pharmaceuticals

Reata Pharmaceuticals (RETA) was a clinical-stage biopharmaceutical company until the U.S. Food and Drug Administration (FDA) approved its first treatment on Feb. 28, 2023. The positive approval decision pushed the stock more than 100% higher overnight, and there could be more fuel in the tank.

Reata's first approved product, Skyclarys, is the first and only drug approved to treat Friedreich's ataxia, an ultra-rare neuromuscular disease. It is often diagnosed during adolescence. Light fatigue typically progresses to wheelchair reliance or further motor impairment before patients reach their 30th birthday. 

Friedreich's ataxia affects roughly 5,000 patients in the U.S. and perhaps 22,000 worldwide. The company plans to launch Skyclarys in the second quarter at a list price of $370,000 annually.

A successful launch could drive global Skyclarys sales past $1 billion at its peak, but this stock's market cap is still just $3.3 billion. Biotech stocks generally trade at mid-single-digit multiples of sales, so buying this one now and holding on could pay off well if Skyclarys meets expectations.

Calliditas Therapeutics

Shares of Calliditas Therapeutics (CALT 5.95%) recently jumped more than 30% in response to positive clinical trial data for its lead drug Nefecon. The FDA granted this drug conditional approval last year under the brand name Tarpeyo, and the new trial results could be sufficient to ask the agency for full approval.

Nefecon is an oral formulation of budesonide, a decades-old steroid treatment typically found in asthma inhalers. It's also the first treatment approved by the FDA for patients with IgA nephropathy.

The latest trial results involve 9 months of treatment with Nefecon plus 15 months of observation. Patients randomized to receive Nefecon showed significant kidney function improvements over the placebo group.

Full approval is exactly what Nefecon needs to help gain a larger share of the limited IgA patient population. In February, the FDA granted a second drug, Filspari from Travere Therapeutics, conditional approval to treat IgA nephropathy patients too.

With a market cap of just $719 million, expectations for Calliditas aren't very high. This means even a moderately successful launch for Nefecon could drive the stock to new heights.

NeoGenomics

NeoGenomics (NEO -1.74%) stock has already climbed more than 100% in 2023. The company specializes in cancer genetics testing. This is an increasingly lucrative corner of the diagnostics industry because nearly every new cancer drug targets specific genetic mutations.

Shares of this diagnostic stock are way up this year because it looks like last year's executive suite shakeup is working out well for investors. Last August, a new CEO took the helm, and the operational improvements he made have already encouraged multiple Wall Street analysts to upgrade the stock to a buy.

Last year, the company launched RaDaR, a minimal residual disease test for cancer patients in remission. After reporting heavy losses in 2022, the company expects adjusted earnings before interest, taxes, depreciation, and amortization (EBITDA) to turn positive in the fourth quarter of this year with help from the RaDaR launch.

Know the risks

While all three of these stocks could keep climbing, you're probably better off looking for less risky places to put your money. Reata and Calliditas could soar further if their drug launches achieve some lofty goals. Unfortunately, independent drug launches without big pharma backing rarely meet expectations.

NeoGenomics and its new CEO are making progress on a promise to reach profitability. Given the highly competitive nature of the diagnostics industry, though, it's probably better to watch from the sidelines until after the company can report positive earnings.