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OBI-999
OBI-999 is an antibody-drug conjugate targeting Globo H carbohydrate antigen on cancer cells to deliver cytotoxic payload.
OBI-999 is a Globo H-targeting antibody-drug conjugate (ADC) developed by OBI Pharma for advanced solid tumors. The drug works by binding to Globo H, a carbohydrate antigen overexpressed on cancer cells, and delivering a cytotoxic payload to induce tumor cell death. OBI-999 entered clinical development with a first-in-human study published in JCO Precision Oncology (2023), demonstrating preliminary activity in patients with advanced solid tumors. The program has been discontinued, indicating the company did not advance the asset to later-stage development or chose to reallocate resources. As a Globo H-targeting ADC, OBI-999 represented a differentiated approach to solid tumor treatment, though clinical efficacy or safety concerns likely contributed to the discontinuation decision. The asset remains notable in the ADC landscape as an example of carbohydrate antigen targeting in oncology.
At a glance
| Generic name | OBI-999 |
|---|---|
| Sponsor | OBI Pharma, Inc |
| Drug class | Antibody-drug conjugate (ADC) |
| Target | Globo H (globoside carbohydrate antigen) |
| Modality | Small molecule |
| Therapeutic area | Oncology |
| Phase | discontinued |
Mechanism of action
OBI-999 functions as an antibody-drug conjugate (ADC), a biotherapeutic combining monoclonal antibody specificity with chemotherapy potency. The antibody component recognizes and binds to Globo H, a carbohydrate antigen that is overexpressed on the surface of many advanced solid tumors but has limited expression on normal tissues. Once the OBI-999 antibody binds to Globo H on tumor cells, the complex is internalized through receptor-mediated endocytosis. Inside the cell, the linker connecting the antibody to the cytotoxic payload is cleaved, releasing the active drug to disrupt microtubule dynamics and induce apoptosis. This mechanism allows selective delivery of chemotherapy to tumor cells while minimizing exposure to healthy tissue, potentially improving the therapeutic window compared to conventional chemotherapy.
Approved indications
Pipeline indications
- Advanced solid tumors — Phase 1
Common side effects
Key clinical trials
- Phase 1/2 Study of OBI-999 in Patients With Advanced Solid Tumors (PHASE1, PHASE2)
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
Competitive intelligence
For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:
- OBI-999 CI brief — competitive landscape report
- OBI-999 updates RSS · CI watch RSS
- OBI Pharma, Inc portfolio CI