In short
PF-08634404 is an investigational protein-based medicine being studied in clinical trials for several advanced cancers. It is a tetravalent bispecific antibody targeting PD-1 and VEGF, and it has no marketing authorisation yet. The current research programme includes ten authorised trials covering conditions such as metastatic colorectal cancer, non-small cell lung cancer, small cell lung cancer, hepatocellular carcinoma, renal cell carcinoma, and gastroesophageal cancers.
Key points
- PF-08634404 is an investigational bispecific antibody targeting PD-1 and VEGF, studied in oncology.
- The clinical programme includes ten authorised trials across multiple advanced solid tumours.
- The largest trial enrols 1,410 participants with locally advanced or metastatic non-small cell lung cancer.
- Several trials are in Phase 3, comparing PF-08634404 combinations against standard therapies.
- Early-phase trials measure objective response rate (ORR) and safety, including dose-limiting toxicities.
- PF-08634404 is given as a concentrate for solution for infusion by intravenous administration.
What is PF-08634404?
PF-08634404, also known by the development code SSGJ-707, is an investigational protein-based substance being developed by Pfizer Inc. It is described in a published trial-in-progress article as a tetravalent bispecific antibody targeting PD-1 and VEGF. The substance has no marketing authorisation in the product records and remains an investigational medicine.
How does PF-08634404 work?
As a bispecific antibody, PF-08634404 is designed to bind to two different targets at the same time: the immune checkpoint protein PD-1 and the vascular endothelial growth factor (VEGF). PD-1 is a protein on immune cells that can dampen the immune response against cancer, while VEGF is a growth factor that helps tumours build new blood vessels. By blocking both targets, the antibody aims to support the immune system's ability to attack cancer cells and to interfere with the tumour's blood supply. This dual mechanism is being evaluated across several tumour types in the current trial programme.
Which conditions is PF-08634404 studied for?
- Metastatic colorectal cancer — a Phase 3 trial is testing PF-08634404 with chemotherapy against bevacizumab with chemotherapy.
- Locally advanced or metastatic non-small cell lung cancer — a Phase 3 trial is comparing PF-08634404 plus chemotherapy with pembrolizumab plus chemotherapy.
- Extensive-stage small cell lung cancer — a Phase 4 trial is evaluating PF-08634404 in combination with chemotherapy.
- Unresectable locally advanced or metastatic hepatocellular carcinoma — a Phase 1 trial is studying PF-08634404 alone and with ipilimumab.
- Advanced solid tumours — a Phase 1 trial is testing PF-08634404 with other anticancer agents.
- Locally advanced or metastatic renal cell carcinoma — a Phase 1 trial is evaluating PF-08634404 alone and in combinations.
- Locally advanced or metastatic urothelial cancer — a Phase 1 trial is studying PF-08634404 alone and with enfortumab vedotin.
- Transformed small cell lung cancer — a Phase 2 trial is testing PF-08634404 with chemotherapy.
- Locally advanced or metastatic gastric, gastroesophageal junction, or esophageal adenocarcinoma — a Phase 4 trial is comparing PF-08634404 plus chemotherapy with nivolumab plus chemotherapy.
- Early-stage resectable or locally advanced unresectable non-small cell lung cancer — a Phase 2 trial is evaluating PF-08634404 as neoadjuvant, adjuvant, and consolidation therapy.
How is PF-08634404 given?
PF-08634404 is supplied as a concentrate for solution for infusion and is given by intravenous administration. In the trial records, the route of administration is listed as unknown use in some cases, but the pharmaceutical form indicates that the medicine is prepared as an infusion. Doses are reported per kilogram of body weight in several trials.
What do the clinical trials show?
The clinical programme for PF-08634404 currently includes ten authorised interventional trials. The conditions studied span several advanced solid tumours, with the largest trials in lung and gastrointestinal cancers. The table below summarises the key features of each trial.
| Trial identifier | Phase | Condition | Status | Participants |
|---|---|---|---|---|
| NCT07222800 | Phase 3 | Metastatic colorectal cancer | Authorised | 800 |
| NCT07222566 | Phase 3 | Locally advanced or metastatic non-small cell lung cancer | Authorised | 1410 |
| NCT07226999 | Phase 4 | Extensive-stage small cell lung cancer | Authorised | 540 |
| NCT07227012 | Phase 1 | Unresectable locally advanced or metastatic hepatocellular carcinoma | Authorised | 138 |
| NCT07227298 | Phase 1 | Advanced solid tumours | Authorised | 162 |
| NCT07227415 | Phase 1 | Locally advanced or metastatic renal cell carcinoma | Authorised | 224 |
| 2025-523523-21-00 | Phase 1 | Locally advanced or metastatic urothelial cancer | Authorised | 132 |
| NCT07476287 | Phase 2 | Transformed small cell lung cancer | Authorised | 40 |
| NCT07392892 | Phase 4 | Locally advanced or metastatic gastric, gastroesophageal junction, or esophageal adenocarcinoma | Authorised | 840 |
| 2025-524825-42-00 | Phase 2 | Early-stage resectable or locally advanced unresectable non-small cell lung cancer | Authorised | 120 |
What are the trials measuring?
The later-phase trials focus on survival outcomes. In metastatic colorectal cancer, the primary outcomes are progression-free survival (PFS) assessed by blinded independent central review (BICR) and overall survival (OS). In locally advanced or metastatic non-small cell lung cancer, the trial also measures OS and PFS using RECIST v1.1 as assessed by BICR. The extensive-stage small cell lung cancer trial includes OS as a Phase 3 outcome and confirmed objective response rate (ORR) plus adverse events as Phase 2 outcomes. The gastroesophageal cancer trial measures PFS and OS in Phase 3, and ORR and adverse events in Phase 2. Early-phase trials measure confirmed ORR according to RECIST 1.1, dose-limiting toxicities (DLTs), and adverse events characterised by type, frequency, and severity.
Who can take part in these trials?
All ten trials enrol adult participants. The specific eligibility criteria vary by trial and condition. For example, the metastatic colorectal cancer trial is for adults with metastatic colorectal cancer, while the non-small cell lung cancer trials include participants with locally advanced or metastatic disease, as well as those with early-stage resectable or locally advanced unresectable disease in a separate Phase 2 trial. The hepatocellular carcinoma and renal cell carcinoma trials focus on participants with unresectable or advanced disease, and the urothelial cancer trial includes participants with previously treated or untreated locally advanced or metastatic disease depending on the cohort.
What side effects are known?
The published trial-in-progress article does not report specific side effects for PF-08634404. The ongoing trials are collecting safety information, including adverse events characterised by type, frequency, severity, timing, seriousness, and relationship to the study intervention. Results from these trials will provide a fuller picture of the safety profile.