Michael O'Donnell

Upon successful screening and registration, enrollment to a cohort will begin. If DLT criteria are exceeded in a cohort, that cohort will close and will not proceed to Phase 2 of the study. Provided the safety of a cohort is established, enrollment will continue. Within BCG-containing cohorts, treatment will begin at full-dose BCG. If DLT criteria are exceeded with full-dose BCG, a one level dose reduction of BCG will be implemented. If DLT criteria are exceeded with reduced-dose BCG, the BCG-containing cohort will not proceed to Phase 2 of the study

Phase 1 Cohorts:

* Durvalumab Monotherapy (cohort 1); ENROLLMENT COMPLETE
* Durvalumab plus BCG (cohort 2); ENROLLMENT COMPLETE
* Durvalumab plus External Beam Radiotherapy (EBRT) (cohort 3); ENROLLMENT COMPLETE
* Durvalumab plus Intravesical Gemcitabine plus Intravesical Docetaxel (cohort 4); ENROLLMENT COMPLETE
* Durvalumab plus Tremelimumab plus Intravesical Gemcitabine plus Intravesical Docetaxel (cohort 5); ENROLLMENT DID NOT OCCUR
* Intravesical N-803NAI plus Intravesical Gemcitabine (cohort 6)
* Intravesical N-803NAI plus Intravesical Gemcitabine plus Intravesical Docetaxel (cohort 7)
* Subcutaneous N-803NAI plus Intravesical N-803NAI plus Intravesical Gemcitabine plus Intravesical Docetaxel (cohort 8)

If any of the combination regimen cohorts establishes a RP2D in Phase 1 of the study, enrollment to Phase 2 of the study may proceed within the individual phase 2 expansion cohorts defined by patient BCG exposure history. Upon successful screening and registration, Phase 2 subjects will be assigned to one of the treatment arms. Assignment will occur amongst the arms that are open to accrual at the time of subject registration. Phase 2 subjects will be administered treatment at the RP2D's established for each regimen within Phase 1 of the study.

However, within BCG-containing cohorts, the BCG dose will be reduced to Dose level -1 (1/3rd-dose BCG) even if the RP2D established in the Phase 1 of the study was full-dose BCG. The rationale for this stems from ongoing global BCG supply shortages that have arisen since the launch of the trial and multiple prior clinical trials demonstrating similar efficacy with decreased toxicity when reduced-dose BCG regimens are utilized compared to full-dose BCG therapy. This modification was deemed necessary to facilitate continued enrollment to the study while not sacrificing clinical efficacy or safety. This modification also aligns with recent AUA consensus guidelines on BCG dosing during BCG shortages.

It is anticipated that individual treatment cohorts will be closed and added during the conduct of the study as cohorts complete accrual, individual cohort safety data is analyzed, and new cohorts are added. Enrollment to Phase 2 cohorts will not begin until at least one cohort has successfully established a RP2D in the Phase 1 portion of the study and deemed safe to proceed to the Phase 2 portion of the trial.

The purpose of this study is to learn how a new medicine called PF-08052667 works when used by itself or together with another medicine called Bacillus Calmette Guerin (BCG), and/or a medicine called sasanlimab.

This study is for adults who have a type of bladder cancer that hasn't spread into the muscle layer of the bladder but is more likely to come back or grow. It includes people whose cancer has come back or hasn't gone away after receiving standard treatments like BCG. It may also include people who, based on their doctor's opinion, cannot receive standard treatments or those treatments are not available to them.

The study has three parts:

* Part 1 (monotherapy dose escalation) will test PF-08052667 as a single-agent at increasing dose levels in participants with certain bladder cancer whose disease has worsened on or after standard treatments.
* Part 2 (combination dose escalation) will test PF-08052667 in combination with BCG and/or sasanlimab (fixed dose) in participants with certain bladder cancer whose disease has worsened on or after standard treatments.
* Part 3 (dose optimization and expansion) will further test PF-08052667 as a single agent or in combination with BCG and/or sasanlimab, at the dose(s) based on findings from Part 1 and Part 2 in participants with certain bladder cancer including those who has never received standard treatments.

All participants will receive the study drug PF-08052667. Only participants in Part 2 and Part 3 of the study will also receive BCG and/or sasanlimab. PF-08052667 will be given as an intravesical infusion, which means it will be injected directly into the bladder. Sasanlimab will be given as a subcutaneous injection, which means it will be injected under the skin.

For all parts, treatment with study medicines will continue until either a participant has decided to stop taking part in the study or is asked to leave the study for various reasons or up to about 2 years, whichever occurs first. Duration of trial participation for each participant will vary as long-term follow-up will continue after treatment discontinuation until loss to-follow-up or death, or until the study is stopped by the sponsor.

The goal of this clinical trial is to learn whether a combination of two chemotherapy drugs, Gemcitabine and Docetaxel, can treat high-grade non-muscle-invasive bladder cancer (HG-NMIBC) in adults whose cancer failed conventional BCG therapy. The drugs are given directly into the bladder (intravesically), one immediately after the other.

The study will also assess the safety of this treatment.

The main questions it aims to answer are:

Can this drug combination effectively treat HG-NMIBC that did not respond to BCG and help prevent the cancer from coming back, offering long-term protection? What side effects or medical issues do participants experience during treatment?

Researchers will evaluate this non-surgical approach as a potential alternative to bladder removal surgery (radical cystectomy), with the goal of validating it as a bladder-sparing option in this setting.

Participants will:

* Go through a screening process, including tumor removal and imaging tests
* Receive weekly bladder treatments with Gemcitabine followed by Docetaxel for 6 weeks
* If the cancer responds, continue with similar once monthly treatments (maintenance therapy) for up to 2 years
* Attend regular check-ups, including bladder exams, urine tests, biopsies, and optional quality-of-life surveys
* Possibly receive a second 6-week treatment cycle if the cancer returns early
* Be followed for up to 5 years to monitor long-term outcomes

This is a phase II, single arm, Simon two-stage design, trial, enrolling patients with cisplatin ineligible MIBC and/or those patients who decline cisplatin based NAC.

Assess rates of pathologic downstaging and quality of life in MIBC cisplatin-ineligible/declined patients when IVC is added to gemcitabine-carboplatin NAC.