Rapt Therapeutics Stock Price, News & Analysis

RAPT Therapeutics, Inc. (Nasdaq: RAPT) is a clinical-stage, immunology-based biopharmaceutical company focused on discovering, developing and commercializing novel therapies for patients living with inflammatory and immunological diseases. According to the company’s public disclosures, RAPT applies what it describes as deep and proprietary expertise in immunology to design drug candidates that modulate critical immune responses underlying these conditions.

Business focus and therapeutic areas

RAPT is engaged in research and development in biotechnology, with a particular emphasis on allergic and other immune-mediated diseases. The company highlights large IgE-driven indications such as food allergy and chronic spontaneous urticaria (CSU) as important areas of focus. Its programs are positioned in the clinical stage, meaning they are being evaluated in human trials rather than only preclinical research.

RAPT has described itself as working to develop a differentiated anti-IgE therapy for patients with food allergies and other allergic inflammatory diseases. The company’s public communications emphasize the goal of addressing unmet medical needs in inflammatory and immunological conditions by targeting key immune pathways.

Key pipeline program: ozureprubart (RPT904)

A central program in RAPT’s pipeline is ozureprubart, formerly known as RPT904. RAPT describes ozureprubart as a novel, half-life extended anti-IgE bio-better monoclonal antibody (mAb) that targets the same epitope as omalizumab for the treatment of patients with food allergy, chronic spontaneous urticaria and other allergic inflammatory diseases. The company states that ozureprubart is designed to inhibit free and cell-bound human immunoglobulin E (IgE), which it identifies as a key driver of allergic diseases.

According to RAPT, early clinical studies of ozureprubart have demonstrated extended pharmacokinetics and pharmacodynamic properties compared to omalizumab, which it characterizes as a first-generation anti-IgE monoclonal antibody. RAPT has also reported positive topline data from a Phase 2 trial of ozureprubart (also referenced as RPT904 or JYB1904) in chronic spontaneous urticaria conducted by its partner Shanghai Jeyou Pharmaceutical Co., Ltd. in China, noting that dosing every 8 or 12 weeks showed comparable efficacy and safety to omalizumab dosed every 4 weeks in that study.

Clinical development activities

RAPT’s disclosures describe multiple ongoing and planned clinical activities around ozureprubart. The company has announced that the U.S. Food and Drug Administration (FDA) cleared its Investigational New Drug (IND) application to proceed to a Phase 2b clinical trial of ozureprubart in food allergy. This Phase 2b trial, referred to as the prestIgE study, is described as a randomized, double-blind, placebo-controlled trial designed to evaluate the safety and efficacy of ozureprubart administered every 8 weeks (Q8W) or every 12 weeks (Q12W) in participants with IgE-mediated food allergy.

RAPT has also reported that it initiated the prestIgE Phase 2b trial in IgE-mediated food allergy, involving multiple sites in the United States, Canada and Australia. The company has indicated that this trial will evaluate ozureprubart monotherapy in participants with at least one food allergy to peanut, milk, egg, walnut or cashew, with treatment and follow-up periods designed to assess responses using double-blind, placebo-controlled oral food challenges.

In chronic spontaneous urticaria, RAPT and its partner Jeyou have announced positive topline data from a randomized, double-blind Phase 2 trial comparing RPT904 dosed every 8 or 12 weeks to omalizumab dosed every 4 weeks. The companies reported numerically greater improvements in the seven-day urticaria activity score (UAS7) and numerically higher proportions of patients achieving UAS7=0 at multiple time points for the RPT904 arms compared to omalizumab in that study, and indicated that these results support advancing the program to Phase 3 development in CSU.

Broader pipeline and historical programs

In addition to ozureprubart, RAPT has previously described pipeline product candidates in oncology and inflammatory diseases. Earlier descriptions reference small-molecule programs such as FLX475, designed to selectively inhibit the migration of immunosuppressive regulatory T cells into tumors, and RPT193, designed to selectively inhibit the migration of type 2 T helper cells into inflamed tissues. More recent financial disclosures reference development activities and cost trends related to programs named zelnecirnon and tivumecirnon, alongside ozureprubart and early-stage programs, indicating that RAPT has pursued multiple immunology-focused assets over time.

Financial and corporate context

RAPT trades on the Nasdaq Stock Market under the ticker symbol RAPT. As a clinical-stage biopharmaceutical company, it reports that it incurs significant research and development expenses related to clinical trials, early-stage programs and associated personnel and facilities. Recent filings describe net losses and operating expenses driven primarily by research and development and general and administrative costs, reflecting its focus on advancing pipeline candidates rather than generating commercial product revenue.

The company has used public equity offerings to fund its operations. For example, RAPT disclosed entering into an underwriting agreement for a public offering of common stock, with gross proceeds of approximately $250 million and estimated net proceeds of approximately $234.4 million, and stated that, based on its current operating plans, it expects that its cash, cash equivalents and marketable securities, together with the offering proceeds, would be sufficient to fund operations into 2028. These statements underscore the capital-intensive nature of late-stage clinical development in biotechnology.

Partnerships and geographic trial activity

RAPT’s collaboration with Shanghai Jeyou Pharmaceutical Co., Ltd. is a notable element of its development strategy. Jeyou conducted the Phase 2 trial of RPT904 in chronic spontaneous urticaria in China and plans to advance the program to Phase 3 development in that market. RAPT has indicated that it intends to discuss a Phase 3 development path for ozureprubart in CSU with the FDA and other regulatory authorities, while also advancing its own trials in food allergy.

The company has also described clinical trial activity for ozureprubart in multiple regions, including sites in the United States, Canada and Australia for the prestIgE Phase 2b food allergy trial. These disclosures highlight that RAPT’s clinical development spans multiple countries through both internal trials and partnered studies.

Industry positioning

Within the broader biotechnology and pharmaceutical landscape, RAPT characterizes itself as an immunology-based biopharmaceutical company focused on inflammatory and immunological diseases, with particular emphasis on IgE-mediated allergic conditions such as food allergy and chronic spontaneous urticaria. Its programs are designed to target specific immune pathways, including IgE and other immune cell mechanisms described in its public materials. As a clinical-stage company, its value proposition centers on the potential of its pipeline candidates and its stated expertise in immunology-driven drug discovery and development.

Frequently asked questions about RAPT Therapeutics

The following questions and answers summarize key points from RAPT’s public disclosures and may help investors and observers understand the company’s focus and activities.