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Ontorpacept (TTI-621) (ontorpacept-tti-621)
Ontorpacept (TTI-621) (generic name: ontorpacept-tti-621) is a Ontorpacept (TTI-621) will be administered by intravenous infusion. drug developed by Pfizer Inc.. It is currently in discontinued development.
Ontorpacept (TTI-621) will be administered by intravenous infusion.
Ontorpacept (TTI-621) is a CD47-mimetic immunotherapy that blocks the 'don't eat me' signal cancer cells use to evade immune destruction. It is approved for certain hematologic malignancies and works by enabling the patient's own macrophages and immune cells to recognize and eliminate cancer cells more effectively.
At a glance
| Generic name | ontorpacept-tti-621 |
|---|---|
| Sponsor | Pfizer Inc. |
| Drug class | Ontorpacept (TTI-621) will be administered by intravenous infusion. |
| Therapeutic area | Oncology |
| Phase | discontinued |
Mechanism of action
Cancer cells have evolved clever ways to avoid being attacked by the immune system. One of their favorite tricks involves a protein called CD47, which acts like a 'don't eat me' sign on the cancer cell's surface. When immune cells called macrophages see this sign, they leave the cancer cell alone and move on to other threats. Ontorpacept works by mimicking and binding to the receptor on macrophages that normally recognizes this CD47 signal. By occupying this receptor with ontorpacept, the drug essentially blocks the cancer cell's disguise. The macrophages can no longer see the 'don't eat me' signal, so they treat cancer cells like any other foreign invader—by engulfing and destroying them. This is called antibody-dependent cellular phagocytosis, and it's one of the body's oldest and most effective immune weapons. This approach is particularly valuable because it works with the patient's own immune system rather than trying to replace it. By removing one of cancer's key escape mechanisms, ontorpacept helps restore the immune system's natural ability to recognize and eliminate malignant cells, potentially offering patients a new treatment option when other therapies have failed or proven ineffective.
Approved indications
Pipeline indications
- Leiomyosarcoma — discontinued
Common side effects
Key clinical trials
- A Study to Learn About the Study Medicine (Called Ontorpacept or TTI-621) Given Alone and in Combina (discontinued)
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:
- Ontorpacept (TTI-621) CI brief — competitive landscape report
- Ontorpacept (TTI-621) updates RSS · CI watch RSS
- Pfizer Inc. portfolio CI
Frequently asked questions about Ontorpacept (TTI-621)
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What is the generic name of Ontorpacept (TTI-621)?
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Related
- Drug class: All Ontorpacept (TTI-621) will be administered by intravenous infusion. drugs
- Manufacturer: Pfizer Inc. — full pipeline
- Therapeutic area: All drugs in Oncology
Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing