Mastocytosis Pipeline Summary

DelveInsight’s, “Mastocytosis - Pipeline Insight, 2026” report provides comprehensive insights about 10+ companies and 10+ pipeline drugs in Mastocytosis pipeline landscape. It covers the pipeline drug profiles, including clinical and nonclinical stage products. It also covers the therapeutics assessment by product type, stage, route of administration, and molecule type. It further highlights the inactive pipeline products in this space.

Geography Covered

• Global coverage

Mastocytosis: Understanding

Mastocytosis: Overview

Mastocytoma is a tumor composed of mast cells, which originate from myeloid stem cells and are primarily found in connective tissues, particularly the skin and mucosal linings. Mast cells contain granules rich in histamine, peptides, and other mediators that contribute to immune and allergic responses. Clonal proliferation of abnormal mast cells can result in localized or systemic disease, collectively termed mastocytosis, a myeloproliferative disorder. While most patients have skin involvement, cutaneous mastocytosis is confined to the skin, whereas systemic mastocytosis affects one or more extracutaneous organs. In adults, mastocytosis is typically chronic and systemic, while cutaneous disease is more common in children and can range from solitary mastocytoma to diffuse disease, most commonly presenting as maculopapular lesions known as urticaria pigmentosa.

The exact cause of mastocytosis remains unclear; however, increased growth factors and interleukins in affected tissues may promote mast cell and melanocyte proliferation while inhibiting mast cell apoptosis. Somatic gain-of-function mutations in the KIT gene, particularly D816V, are present in more than 90% of adults and contribute to abnormal mast cell proliferation through constitutive KIT receptor activation. Although primarily somatic, rare familial cases with autosomal dominant inheritance have also been reported.

Mast cell accumulation typically presents as maculopapular or nodular lesions, with rubbing or pressure triggering mast cell degranulation and the release of histamine, leukotrienes, and prostaglandins, resulting in localized or systemic symptoms. Histologically, mastocytosis is characterized by a dermal infiltrate of mast cells, predominantly in the papillary dermis, often arranged around blood vessels and accompanied by edema and eosinophils. Although diagnostic thresholds vary, higher mast cell densities are generally considered supportive of diagnosis. Mast cells typically appear spindle- to round-shaped with pale, granular cytoplasm and nuclei, while overt nuclear atypia is uncommon and may suggest malignant transformation. Special stains such as Giemsa or toluidine blue highlight metachromatic granules, while expression of tryptase, CD117, and KIT confirms mast cell origin. Aberrant expression of CD25 and, less frequently, CD2 may further support the neoplastic nature of mast cells.

Cutaneous mastocytosis or mastocytoma is primarily suspected based on lesion appearance and a positive Darier sign, with histopathological and molecular testing used for confirmation and to exclude systemic disease. Biopsy demonstrates dermal mast cell infiltration, while tryptase, CD117, and KIT staining confirms mast cell origin; CD25 and CD2 expression may support neoplastic proliferation. Baseline serum tryptase and complete blood counts are recommended, with bone marrow evaluation and abdominal ultrasonography considered in patients with systemic symptoms or evidence of extracutaneous involvement.

Treatment is primarily symptomatic and focuses on minimizing triggers such as friction, temperature changes, and dryness that can promote mast cell mediator release. Oral antihistamines are generally first-line, while topical or intralesional corticosteroids and topical tacrolimus may help relieve cutaneous symptoms; phototherapy can also be considered for persistent pruritus. Cytoreductive and surgical approaches are mainly reserved for systemic disease, with surgical excision also considered for large solitary lesions or cosmetic reasons. Epinephrine is indicated in cases of suspected anaphylaxis. In children with solitary cutaneous mastocytoma, close monitoring is generally preferred, as most benign lesions resolve spontaneously before puberty.

"Mastocytosis- Pipeline Insight, 2026" report by DelveInsight outlays comprehensive insights of present scenario and growth prospects across the indication. A detailed picture of the Mastocytosis pipeline landscape is provided which includes the disease overview and Mastocytosis treatment guidelines. The assessment part of the report embraces, in depth Mastocytosis commercial assessment and clinical assessment of the pipeline products under development. In the report, detailed description of the drug is given which includes mechanism of action of the drug, clinical studies, NDA approvals (if any), and product development activities comprising the technology, Mastocytosis collaborations, licensing, mergers and acquisition, funding, designations and other product related details.

Report Highlights

• The companies and academics are working to assess challenges and seek opportunities that could influence Mastocytosis R&D. The therapies under development are focused on novel approaches to treat/improve Mastocytosis.

Mastocytosis Emerging Drugs Chapters

This segment of the Mastocytosis report encloses its detailed analysis of various drugs in different stages of clinical development, including Phase III, II, I, Preclinical and Discovery. It also helps to understand clinical trial details, expressive pharmacological action, agreements and collaborations, and the latest news and press releases.

Mastocytosis Emerging Drugs

Masitinib: AB Science

Masitinib is an investigational, orally administered tyrosine kinase inhibitor developed by AB Science for the treatment of severely symptomatic indolent systemic mastocytosis (ISM) and smouldering systemic mastocytosis (SSM). It targets key kinases involved in mast-cell proliferation and activation, including wild-type c-KIT, Lyn, and Fyn, thereby reducing mast-cell activity and mediator release. Importantly, its mechanism may provide activity regardless of KIT D816V mutation status. In a Phase III study, masitinib demonstrated greater improvement than placebo in severe mastocytosis-related symptoms, including pruritus, flushing, depression, and fatigue, along with reductions in serum tryptase and Darier’s sign. AB Science has subsequently pursued a confirmatory Phase III program, positioning masitinib as a potential targeted treatment for patients with symptomatic indolent or smouldering systemic mastocytosis who have substantial disease burden. According to company’s pipeline the therapy is in phase III stage of its development for the treatment of indolent systemic mastocytosis.

SEP-631: Septerna

SEP-631 is an investigational, orally administered small-molecule negative allosteric modulator (NAM) of MRGPRX2 being developed by Septerna for mast cell-driven diseases, initially targeting chronic spontaneous urticaria (CSU). MRGPRX2 is a key receptor mediating IgE-independent mast-cell activation and degranulation, leading to the release of inflammatory mediators associated with itching, pain, inflammation, and edema. SEP-631 binds to a distinct allosteric site on MRGPRX2 and potently inhibits receptor activation and subsequent mast-cell degranulation; preclinical studies demonstrated inhibition of degranulation in primary human skin mast cells and skin vascular extravasation in humanized MRGPRX2 models. Currently, the drug is in Phase I stage of its development for the mastocytosis (mast cell mediated disease)

ATH-097: Atheron Therapeutics

ATH-097 is an investigational, orally active small-molecule antagonist of Mas-related G-protein-coupled receptor X2 (MRGPRX2), a mast-cell receptor involved in IgE-independent mast-cell activation and degranulation. Developed by Atheron Therapeutics, ATH-097 has demonstrated potent inhibition of MRGPRX2-mediated mast-cell degranulation in both in vitro and in vivo studies, supporting its potential as a treatment for mast-cell–mediated disorders. The program is being explored in conditions including mastocytosis, chronic spontaneous urticaria, atopic dermatitis, and migraine, with Atheron highlighting its potential to address diseases driven by non-IgE-mediated mast-cell activation. According to company’s pipeline the drug is in preclinical stage of it’s development for the treatment of Mastocytosis.

Further product details are provided in the report……..

Mastocytosis: Therapeutic Assessment

This segment of the report provides insights about the different Mastocytosis drugs segregated based on following parameters that define the scope of the report, such as:

• Major Players in Mastocytosis
• There are approx. 10+ key companies which are developing the therapies for Mastocytosis. The companies which have their Mastocytosis drug candidates in the most advanced stage, i.e. Phase III include, AB Science.

• Phases

DelveInsight’s report covers around 10+ products under different phases of clinical development like

• Late stage products (Phase III)
• Mid-stage products (Phase II)
• Early-stage product (Phase I) along with the details of
• Pre-clinical and Discovery stage candidates
• Discontinued & Inactive candidates

• Route of Administration

Mastocytosis pipeline report provides the therapeutic assessment of the pipeline drugs by the Route of Administration. Products have been categorized under various ROAs such as

• Oral
• Intravenous
• Subcutaneous
• Parenteral
• Topical

• Molecule Type

Products have been categorized under various Molecule types such as

• Recombinant fusion proteins
• Small molecule
• Monoclonal antibody
• Peptide
• Polymer
• Gene therapy

• Product Type

Drugs have been categorized under various product types like Mono, Combination and Mono/Combination.

Mastocytosis: Pipeline Development Activities

The report provides insights into different therapeutic candidates in Phase III, II, I, preclinical and discovery stage. It also analyses Mastocytosis therapeutic drugs key players involved in developing key drugs.

Pipeline Development Activities

The report covers the detailed information of collaborations, acquisition and merger, licensing along with a thorough therapeutic assessment of emerging Mastocytosis drugs.

Mastocytosis Report Insights

• Mastocytosis Pipeline Analysis
• Therapeutic Assessment
• Unmet Needs
• Impact of Drugs

Mastocytosis Report Assessment

• Pipeline Product Profiles
• Therapeutic Assessment
• Pipeline Assessment
• Inactive drugs assessment
• Unmet Needs

Key Questions

Current Treatment Scenario and Emerging Therapies:

• How many companies are developing Mastocytosis drugs?
• How many Mastocytosis drugs are developed by each company?
• How many emerging drugs are in mid-stage, and late-stage of development for the treatment of Mastocytosis?
• What are the key collaborations (Industry–Industry, Industry–Academia), Mergers and acquisitions, licensing activities related to the Mastocytosis therapeutics?
• What are the recent trends, drug types and novel technologies developed to overcome the limitation of existing therapies?
• What are the clinical studies going on for Mastocytosis and their status?
• What are the key designations that have been granted to the emerging drugs?

Key Players

• Atheron
• AB Science
• AllerGene Ai Therapeutics
• Santanna Bio
• Septerna
• Sanofi

Key Products

• ATH-097
• Mastinib
• Research Program: Mastocytosis
• SAB01
• SEP-631
• Elenestinib