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Recruiting Phase 2, Phase 3 NCT07226999

NCT07226999 Symbiotic-Lung-04: A Study to Learn About the Study Medicine Called PF-08634404 in Combination With Chemotherapy in Adult Participants With Extensive-Stage Small Cell Lung Cancer

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Clinical Trial Summary
NCT ID NCT07226999
Status Recruiting
Phase Phase 2, Phase 3
Sponsor Pfizer
Condition Small Cell Lung Cancer (SCLC)
Study Type INTERVENTIONAL
Enrollment 550 participants
Start Date 2025-12-09
Primary Completion 2030-06-14

Eligibility & Interventions

Sex All sexes
Min Age 18 Years
Max Age N/A
Study Type INTERVENTIONAL
Interventions
PF-08634404AtezolizumabChemotherapy

Eligibility Fast-Check

Enter your details for a quick preliminary check. This does not replace medical advice.

What to Expect as a Participant

You will actively receive the study intervention — which may be a drug, biologic, device, or procedure.

In Phase 2, researchers evaluate early signs of effectiveness. You may be randomized to receive the active treatment or a comparator. Monitoring continues closely.

This trial targets 550 participants in total. It began in 2025-12-09 with a primary completion date of 2030-06-14.

⚠ This information is for research awareness only. Always consult your physician before joining any clinical trial. Participation is voluntary and you may withdraw at any time.

Brief Summary

This study is being done to learn more about a new medicine called PF-08634404 and how well it works when given with chemotherapy to adults with extensive-stage small cell lung cancer (ES-SCLC), a fast-growing type of lung cancer that has spread widely in the body. To join the study, participants must meet the following conditions: * Be 18 years or older. * Have extensive-stage small cell lung cancer confirmed by lab tests. * Have not received chemotherapy or radiation for this type of lung cancer. * Be in good physical condition and have healthy organs based on medical tests. The study has two parts: * In the first part, researchers will check how safe the study medicine is and how well people tolerate it when given with chemotherapy. * In the second part, they will compare study medicine plus chemotherapy to another approved treatment (atezolizumab plus chemotherapy) to see which works better. Participants will receive the treatment through IV infusions (medicine given directly into a vein). The treatment will be given in repeated time periods called cycles. Some participants will continue receiving the study medicine alone after the initial treatment.

Eligibility Criteria

Inclusion Criteria: * Histologically or cytologically confirmed extensive-stage small cell lung cancer (ES-SCLC). * Participants have not received systemic therapy (chemotherapy, radiotherapy, chemoradiation) for ES-SCLC. * Treatment-free for at least 6 months since last chemo/radiotherapy, among those treated (with curative intent) with prior chemo/radiotherapy for limited-stage SCLC * Have at least one measurable lesion as the targeted lesion based on RECIST V1.1. * Eastern Cooperative Oncology Group performance status of 0 or 1. * Adequate organ function Exclusion Criteria: * known active CNS lesions, including brainstem, meningeal, or spinal cord metastases or compression * Leptomeningeal disease * Clinically significant risk of hemorrhage or fistula * history of another malignancy within 3 years * active autoimmune diseases requiring systemic treatment within the past 2 years

Contact & Investigator

Central Contact

Pfizer CT.gov Call Center

✉ ClinicalTrials.gov_Inquiries@pfizer.com

📞 1-800-718-1021

Principal Investigator

Pfizer CT.gov Call Center

STUDY DIRECTOR

Pfizer

Frequently Asked Questions

Who can join the NCT07226999 clinical trial?

This trial is open to participants of all sexes, aged 18 Years or older, studying Small Cell Lung Cancer (SCLC). Full inclusion and exclusion criteria are listed in the Eligibility Criteria section. Always confirm your eligibility with the research team before applying.

What phase is the NCT07226999 trial and what does that mean for participants?

Phase 2 trials evaluate whether the treatment shows signs of effectiveness while continuing to monitor safety. More participants are enrolled than in Phase 1 to help refine the treatment protocol.

Is NCT07226999 currently recruiting?

Yes, NCT07226999 is actively recruiting participants. Contact the research team at ClinicalTrials.gov_Inquiries@pfizer.com for enrollment information.

Where is the NCT07226999 trial being conducted?

This trial is being conducted at Fayetteville, United States, Rogers, United States, Springdale, United States, Coral Springs, United States and 11 additional locations.

Who is sponsoring the NCT07226999 clinical trial?

NCT07226999 is sponsored by Pfizer. The principal investigator is Pfizer CT.gov Call Center at Pfizer. The trial plans to enroll 550 participants.

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ClinicalMetric — Independent clinical trial intelligence platform. Not affiliated with NIH, ClinicalTrials.gov, the U.S. FDA, or any pharmaceutical company, hospital, or clinical research organization. Trial data is sourced from ClinicalTrials.gov for informational purposes only and does not constitute medical advice. Do not make any treatment, enrollment, or health decisions based solely on information found here — always consult a qualified healthcare professional. Full Disclaimer  ·  Last Reviewed: July 2026  ·  Data Methodology