RecruitingPhase 2

Symbiotic-Lung-14: A Study to Learn About the Study Medicine Called PF08634404 in Combination With Chemotherapy in Adult Participants With Transformed Small Cell Lung Cancer

United States, Brazil, China40 participantsStarted 2026-07-02

Plain-language summary

This study is being done to learn more about a new medicine called PF-08634404. The study team wants to understand how well PF-08634404 works when given alone or with chemotherapy . Chemotherapy is a type of cancer treatment that uses medicines to destroy cancer cells or stop them from growing. The study is for adults with Transformed Small Cell Lung Cancer (T-SCLC ). T SCLC is a rare lung cancer that happens when one type of lung cancer changes into a more aggressive type after treatment stops working. To join the study, participants must meet the following conditions: * Are aged 18 years or older * Diagnosed with T-SCLC and have not received treatment for this type of lung cancer (a single cycle of chemotherapy may be permitted) * Prior diagnosis of epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer treated with tyrosine kinase inhibitors (TKIs) * Have healthy organs based on medical tests and are in good physical condition After joining the study, adults will be given chemotherapy in addition to the study medicine. After this combination treatment is finished, the study medicine will be continued alone. Adults will receive the treatment through IV infusions (medicine given directly into a vein). All treatments will be done at clinical study sites, where a trained medical team will monitor adults during and after each visit.

Who can participate

Age range

18 Years

Sex

ALL

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Inclusion Criteria: * Male or female participants aged ≥18 years at the time of informed consent. * Histologically or cytologically confirmed T-SCLC. Participant must have had a prior diagnosis of NSCLC with EGFR mutation which transformed to SCLC following the treatment with TKI(s). * Participants have not received systemic therapy for T-SCLC. * Have at least one measurable lesion as the target lesion based on RECIST v1.1. * Have sufficient tumor tissue from the diagnosis of transformed SCLC available. * Eastern Cooperative Oncology Group performance status of 0 or 1. * Have a minimum life expectancy of \>12 weeks. * Clinical laboratory values at screening within acceptable limits, as defined in the protocol, including: 1) Hematology, 2) Liver function and 3) Renal function. Exclusion Criteria: Participants are excluded from the study if any of the following criteria apply: * Active or untreated CNS disease, including brain, brainstem, spinal cord, or meningeal metastases. Participants with definitively treated, clinically stable brain metastases may be eligible per protocol criteria. Participants with untreated asymptomatic brain metastases of longest diameter \<1 cm are permitted if all of the following criteria are met: absence of neurological symptoms, no need for corticosteroids, and brain metastasis has no evidence of edema or hemorrhagic features. * Leptomeningeal disease * Clinically significant risk of hemorrhage or fistula, including tumor necrosis/cavitation, …

Questions worth asking your doctor

Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.

1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?

Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.

Questions for the trial coordinator

The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.

1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?

A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.

What they're measuring

Confirmed Objective Response Rate (ORR) as assessed by investigator based on Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST v1.1)

Timeframe: From start of treatment until first documented CR or PR (approximately maximum up to 1 years)

Number of Participants with Adverse Events (AEs)

Timeframe: Up to 90 days after the last dose of treatment

Trial details

NCT IDNCT07476287

SponsorPfizer

Sponsor typeINDUSTRY

Study typeINTERVENTIONAL

Primary completion2028-03-19

Contact for this trial

Pfizer CT.gov Call Center

1-800-718-1021 ClinicalTrials.gov_Inquiries@pfizer.com

View on ClinicalTrials.gov More Small Cell Lung Cancer trials