A Phase 1 Multiple-Dose Study to Evaluate the Safety and Tolerability of XmAb 22841 Monotherapy and in Combination with Pembrolizumab in Subjects with Selected Advanced Solid Tumors (DUET-4)

Are you eligible to participate in this study?

You may be eligible for this study if you meet the following criteria:

  • Conditions:
    Selected Advanced Solid Tumors
  • Age: Between 18 years - 100 years
  • Gender: Male or Female
  • Other Inclusion Criteria:
    1. All subjects (dose escalation) must have adequate archival tumor sample (slides or archival FFPE block[s] containing tumor that has not been previously irradiated; FFPE blocks are preferred to slides; and newly obtained biopsies are preferred to archived tissue. 2. Subjects have ECOG performance status of 0 – 1. 3. Subjects must have measurable disease by RECIST 1.1 as assessed by the local site investigator or radiology department. 4. For anti-PD1 treatment naive melanoma which would receive XmAb22841 in Combination with chemotherapy, subjects must not have previously been treated with an agent targeting PD1 or PDL1. 5. For the anti-PD1 treatment-refractory melanoma cohorts with XmAb22841 monotherapy or XmAb22841 in combination with pembrolizumab, subjects must have progressed with an anti-PD1/L1 mAb administered either as monotherapy, or in combination with other checkpoint inhibitors or other therapies. 6. For the anti-PD1 treatment-naive NSCLC cohort with XmAb22841 in combination with pembrolizumab, subjects must not have been previously treated with an agent targeting PD1 or PDL1 and have a tumor with high PD-L1 exprsesion (TPS =50%) 7. For the anti-PD1 treatment-refractory NSCLC cohort with XmAb22841 monotherapy or XmAb22841 in combination with pembrolizumab, subjects must have progressed on treatment with an anti-PD1/L1 mAb administered either as monotherapy, in combination with other checkpoint inhibitors, or other therapies. 8. For the anti-PD1 treatment-naive urothelial carcinoma cohort with XmAb22841 in combination with pembrolizumab, subjects must not have previously been treated with an agent targeting PD1 or PDL1 and whose tumors express PDL1 (CPS greater than or equal to 10).

You may not be eligible for this study if the following are true:

  • 1. Prior treatment with an investigational anti-LAG3 therapy. 2. Treatment with any CTLA4 antibody within 16 weeks of the start of study drug. 3. Systemic antineoplastic therapy (including cytotoxic chemotherapy and toxin immunoconjugates), unconjugated antibody therapy within 4 weeks of the first dose of study treatment; or radiotherapy within 2 weeks of the first dose of study treatment; or small molecule kinase inhibitors within 6 elimination half-lives of the first dose of study treatment.


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