Shilpa Biologicals, mAbTree Program Targets Immune Pathway in Rare Blood Cancers

Efforts to expand immunology-driven treatment strategies in rare hematologic cancers are gaining momentum as emerging biologic programs begin targeting immune-evasion pathways implicated in disease persistence. Against this backdrop, Shilpa Biologicals and mAbTree Biologics received orphan drug designation from FDA for an investigational monoclonal antibody (mAb) being developed to treat essential thrombocythemia (ET) and polycythemia vera (PV), the companies announced on March 12, 2026.¹

ET and PV are chronic blood cancers characterized by dysregulated hematopoiesis and persistent inflammatory signaling. Although several therapies are available to manage symptoms and reduce complications, many patients eventually experience incomplete responses, intolerance, or disease progression.²

“This milestone marks a defining moment for Shilpa’s biologics journey and validates the strength of our collaboration with mAbTree Biologics,” said Sridevi Khambhampaty, PhD, CEO, Shilpa Biologics, in a company press release.¹ “[FDA’s] recognition of our flagship biologic underscores the quality of the science and our ability to translate innovation into globally relevant clinical programs. We are advancing rapidly toward clinical development and see strong potential beyond rare blood cancers.”

The investigational therapy is designed to target an immune-evasion pathway implicated in the persistence of myeloproliferative neoplasms, a biological mechanism increasingly recognized as contributing to treatment resistance and ongoing disease activity.

Why is immune dysregulation emerging as a therapeutic target in myeloproliferative neoplasms?

Myeloproliferative neoplasms, including ET and PV, arise from clonal expansion of hematopoietic stem cells that drive excessive production of platelets or red blood cells. These disorders are associated with chronic inflammation and immune dysregulation that may enable malignant cell populations to persist despite therapy.³

Standard treatments, including aspirin, interferon-alpha, hydroxyurea, and Janus kinase inhibitors, have improved disease management and reduced thrombotic complications. However, most therapies focus primarily on controlling disease manifestations rather than directly modifying underlying disease biology.⁴

Investigational immunology-based therapies aim to address this gap by targeting immune pathways that support malignant cell survival. The mAb being developed by Shilpa Biologicals and mAbTree Biologics targets a previously underexplored immune-evasion pathway involved in myeloproliferative neoplasm biology, according to the companies.¹

How could orphan drug designation accelerate development of novel biologics?

For Shilpa Biologicals and mAbTree Biologics, the designation represents an important regulatory milestone as the companies advance the investigational mAb toward clinical evaluation. The program is currently undergoing investigational new drug–enabling studies with the goal of initiating first-in-human clinical trials in patients with essential thrombocythemia and polycythemia vera.

“Receiving [orphan drug designation] from [FDA] is a strong validation of the differentiated mechanism behind this program,” said Raj Andhuvan, CEO, mAbTree Biologics, in the release.¹ “By targeting immune dysregulation—now recognized as a central driver of disease persistence in myeloproliferative neoplasms—this biologic has the potential to establish a new therapeutic paradigm in rare blood cancers.”

The companies also indicated that the mAb, a checkpoint inhibitor, may have potential applications beyond myeloproliferative neoplasms, including exploration in solid tumor settings such as lung cancer and head and neck squamous cell carcinoma.

As biologic drug development increasingly focuses on immune mechanisms across oncology and hematology, therapies targeting immune-evasion pathways may expand treatment strategies for rare cancers with persistent unmet medical need.

References

1. Shilpa Biologicals. Shilpa Biologicals and mAbTree Biologics Secure Orphan Drug Designation from US FDA. Press Release. March 12, 2026.
2. Bose P, Verstovsek S. Updates in the management of polycythemia vera and essential thrombocythemia. Ther. Adv. Hematol. 2019;10:2040620719870052. doi: 10.1177/2040620719870052
3. Mendez Luque LF, Blackmon AL, Ramanathan G, Fleischman AG. Key Role of Inflammation in Myeloproliferative Neoplasms: Instigator of Disease Initiation, Progression. and Symptoms. Curr Hematol Malig Rep. 2019;14(3):145-153. doi: 10.1007/s11899-019-00508-w 
4. Radia D, Geyer HL. Management of symptoms in polycythemia vera and essential thrombocythemia patients. Hematology Am Soc Hematol Educ Program 2015;2015(1): 340–348. doi: 10.1182/asheducation-2015.1.340