What Rarity does

Rarity PBC is a clinical-stage biotechnology company structured as a Public Benefit Corporation, developing ex vivo autologous hematopoietic stem cell (HSC) gene therapies for rare genetic diseases. Its sole clinical asset, RDP-101, is an autologous gene therapy that collects a patient's own blood-forming stem cells, modifies them using a lentiviral vector to deliver a corrected copy of the ADA gene, and reinfuses the cells to restore immune function. The therapy targets Adenosine Deaminase Severe Combined Immunodeficiency (ADA-SCID), a life-threatening inherited immune disorder — commonly called "bubble baby disease" — that affects an estimated 1 in 200,000 to 1 million newborns and is screened for in all 50 U.S. states, D.C., and Puerto Rico.

Rarity's competitive position rests on an exclusive license from UCLA Technology Development Group for the underlying therapy, which was invented by Dr. Donald Kohn at UCLA in collaboration with researchers at University College London and has been administered to approximately 70 patients in clinical trials, with 48 of 50 children in the most recent dataset achieving successful immune reconstitution. The company is pursuing FDA approval and has engaged AGC Biologics as its CDMO using the proprietary ProntoLVV adherent platform for commercial-scale lentiviral vector manufacturing. Development is supported by a $14.7 million California Institute for Regenerative Medicine (CIRM) grant awarded in November 2024 and a $4.6 million seed funding round closed in October 2025 and co-led by biotech investor Steve Oliveira and Nemean Asset Management.

The company's business model is a one-time curative treatment sale model: if approved, RDP-101 would be the first commercially available gene therapy for ADA-SCID in the United States, priced and reimbursed as a single-administration therapy (typical gene therapies in this class command multi-million-dollar prices, though no specific price has been disclosed). Distribution will be conducted through specialized treatment centers capable of stem cell collection, modification, and reinfusion, addressing the ultra-rare pediatric patient population through healthcare providers and payers rather than direct-to-consumer channels. The PBC legal structure formally aligns the company's financial objectives with patient access and affordability mandates.

Name

Rarity

Legal name

Rarity PBC

Website

https://raritypbc.com

Company type

Private

Founded year

2025

Operating status

Operating

Headcount range

1–10 employees

Short description

Rarity PBC is a clinical-stage Public Benefit Corporation developing RDP-101, an ex vivo autologous hematopoietic stem cell gene therapy using a lentiviral vector to treat ADA-SCID (bubble baby disease), serving pediatric patients with this ultra-rare inherited immune disorder via an exclusive UCLA license.

Ownership category

akta.pro rank

Headquarters

HQ city

Los Angeles

HQ country

United States

HQ region

North America

Offices1 record

Markets served

GTM type

B2B

Offering type

Hardware or Manufacturing

Cost components

Technology or R&D, Personnel, Operations, Marketing or Sales, Infrastructure

Revenue model

1. Gene therapy product sales: One-time curative gene therapy treatment for ADA-SCID (RDP-101). If approved by FDA, would be the first gene therapy available for commercial use to reverse ADA-SCID in the United States. Revenue from treatment sales to healthcare providers and payers.

Go-to-market motion1 record

Distribution channels1 record

Marketing channels3 records

Core offering

Rarity PBC develops RDP-101, an ex vivo autologous hematopoietic stem cell gene therapy that modifies a patient's own stem cells using a lentiviral vector to deliver a corrected ADA gene, intended as a one-time curative treatment for ADA-SCID (bubble baby disease). The company is advancing the therapy through GMP manufacturing with AGC Biologics and FDA regulatory approval to make RDP-101 the first commercially available gene therapy for ADA-SCID in the U.S.

Product overview

Rarity PBC operates as a single-product biotechnology company structured as a Public Benefit Corporation. The company's sole product offering is RDP-101, an ex vivo autologous gene therapy for ADA-SCID that modifies a patient's own hematopoietic stem cells using a lentiviral vector to deliver a functional ADA gene. The therapy represents a one-time, potentially curative treatment for ADA-SCID, a rare and life-threatening immune disorder commonly referred to as "bubble baby disease."

Differentiator

Problem solved

Functional benefit

Brands

• RDP-101: Ex vivo autologous hematopoietic stem cell gene therapy for ADA-SCID (Adenosine Deaminase Severe Combined Immunodeficiency), also known as 'bubble baby disease'.

Products and services

• RDP-101 Ex vivo autologous hematopoietic stem cell (HSC) gene therapy for Adenosine Deaminase Severe Combined Immunodeficiency (ADA-SCID, 'bubble baby disease'). A patient's own blood-forming stem cells are collected, modified ex vivo using a lentiviral vector to deliver a functional copy of the ADA gene, and reinfused to restore immune function. Intended as a one-time, potentially curative treatment for infants and children with ADA-SCID; clinical trials have successfully treated 48 of 50 children.

Quantifiable outcome

• 48 out of 50 children successfully treated in clinical trials
• +2 more outcomes

Named customers1 record

Segments1 record

Ideal customer profiles2 records

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature1 record

Partnerships

Two partnerships are on record, tiered core.

• AGC BiologicscoreStrategic or Co-development Partner · 23 October 2025AGC Biologics, a global CDMO, partnered with Rarity PBC to provide end-to-end GMP manufacturing services for RDP-101 gene therapy. Services include process development, GMP manufacturing, and process validation activities required to bring the product to market. AGC will use their proprietary ProntoLVV adherent platform for the lentiviral vector process.
• UCLA Technology Development Group (TDG)coreOEM/ Whitelabel/ Licensing Partner · 14 October 2025Rarity PBC secured an exclusive licensing agreement with UCLA TDG for a groundbreaking gene therapy for ADA-SCID. The therapy was invented and developed by UCLA researcher Dr. Donald Kohn in collaboration with researchers at University College London. This exclusive license is critical for advancing ADA-SCID treatment toward FDA approval.

Scale indicators4 records

Recent moves6 records

Expansion highlights5 records

Direct peers

• Krystal Biotech: Commercial-stage rare disease gene therapy company that developed and commercialized Vyjuvek, the first FDA-approved topical gene therapy. Comparable in focusing on curative single-dose gene therapies for rare genetic conditions and pursuing similar regulatory and commercialization pathways.
• Orchard Therapeutics: Gene therapy company developing ex vivo autologous HSC gene therapies for rare immunodeficiency disorders, including ADA-SCID (Strimvelis was approved in EU). Direct competitor in ADA-SCID space with similar autologous lentiviral approach and rare disease focus.
• bluebird bio: Gene therapy company focused on severe genetic diseases using ex vivo lentiviral vector approaches for rare conditions including beta-thalassemia and sickle cell disease. Comparable in autologous gene therapy methodology and rare disease patient populations.
• Abeona Therapeutics: Clinical-stage gene therapy company developing treatments for rare genetic diseases including recessive dystrophic epidermolysis bullosa. Comparable in mission-driven approach to rare disease gene therapies and similar development stage.

Broad incumbents

• Spark Therapeutics: Pioneer in gene therapy now owned by Roche; developed Luxturna, the first FDA-approved gene therapy for a genetic disease. Comparable in AAV-based gene therapy for rare inherited conditions but operates as part of a much larger organization.
• Ultragenyx Pharmaceutical: Larger commercial-stage rare disease biotech with multiple approved products and gene therapy programs. Comparable in targeting rare genetic disorders but operates a broader diversified portfolio rather than single-asset focus.
• Sangamo Therapeutics: Clinical-stage genomic medicine company developing zinc finger nuclease-based gene therapies for rare diseases including inherited immunodeficiencies. Comparable in rare disease gene therapy approach and autologous cell therapy modality.
• CRISPR Therapeutics: Clinical-stage gene editing company with Casgevy approved for sickle cell disease and beta-thalassemia. Comparable in targeting rare genetic blood disorders with curative intent but uses gene editing rather than gene replacement technology.

Emerging players

• Poseida Therapeutics: Clinical-stage cell and gene therapy company developing non-viral approaches for rare diseases including hematologic malignancies. Comparable in autologous cell therapy development and rare disease focus, with partial overlap in patient populations.
• GenSight Biologics: Clinical-stage gene therapy company focused on rare ophthalmologic and neurodegenerative diseases. Comparable in rare disease gene therapy mission and commercialization challenges, but focuses on different therapeutic areas than ADA-SCID.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat4 records

Key risks5 records

Key highlights7 records

Customer concentration

• LinkedInlinkedin.com/company/raritypbc

Revenue estimate

Valuation estimate

Number of profiles

Profiles8 records

Funding overview

Funding rounds1 record

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Rarity