What happened RAPT Therapeutics (NASDAQ: RAPT) stock was crushing it on Monday, with shares skyrocketing 110.4% as of 11:59 a.m. EDT. The huge gain came after the company announced positive top-line results from a phase 1b clinical study evaluating RPT193 in treating moderate-to-severe atopic dermatitis. So what You'd expect that RAPT's results from the early-stage study of RPT193 had to be fantastic for the biotech stock to more than double. And they were. Patients treated with the company's experimental drug achieved a 36.3% improvement in the Eczema Area and Severity Index (EASI) score from baseline. That was more than twice the 17% improvement seen in patients on a placebo. The story looked even better with patients experiencing a 50% improvement in EASI score -- 42.9% of patients treated with RPT193 achieved this marked improvement compared to only 10% of patients in the placebo group. Image source: Getty Images. RPT193 also achieved the primary efficacy endpoints on two other measurements: the validated Investigator Global Assessment (vIGA) and pruritis Numerical Rating Scale (NRS). The experimental drug appeared to be well tolerated in the early-stage clinical study, with no serious adverse events reported. Investors were especially excited about these results because RPT193 is a once-daily oral treatment. If the drug eventually wins regulatory approval, it could have a competitive advantage over rival treatments that are administered via injection. Now what RAPT Therapeutics now plans to advance RPT193 to a phase 2b study targeting atopic dermatitis. The company will also evaluate the therapy in a phase 2a study in treating asthma. 10 stocks we like better than RAPT Therapeutics, Inc.When investing geniuses David and Tom Gardner have a stock tip, it can pay to listen. After all, the newsletter they have run for over a decade, Motley Fool Stock Advisor, has tripled the market.* David and Tom just revealed what they believe are the ten best stocks for investors to buy right now... and RAPT Therapeutics, Inc. wasn't one of them! That's right -- they think these 10 stocks are even better buys. See the 10 stocks *Stock Advisor returns as of June 7, 2021 Keith Speights has no position in any of the stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. The Motley Fool has a disclosure policy.Source