Lamivudine for Solid Tumors

Inclusion Criteria: * Patients must have a pathologically confirmed diagnosis of a solid malignancy * Patients must have progressed (clinically or radiographically) on or following prior therapy with a PD-1 or PD-L1 targeted antibody * Patients must have exhausted or declined all standard therapies deemed to have significant clinical benefit * Patients may have only 0 or 1 intervening lines of therapy from the prior PD-(L)1 blocking therapy * Patient must be willing and able to provide blood samples (12 green-top tubes, roughly 100mL) at the four time points indicated in the Study Calendar. * Age ≥ 18 years. * ECOG 0-2. The exception will be patients carrying long term disability (such as cerebral palsy) where the disability is not acute nor progressive, and unlikely to significantly affect their response to therapy. This must be documented in screening clinic visit note by investigator. * Women of child-bearing potential and men must agree to use adequate contraception prior to study entry, for the duration of study participation, and for 3 months following completion of therapy. Should a woman become pregnant or suspect she is pregnant while participating in this study, she should inform her treating physician immediately. A female of child-bearing potential is any woman (regardless of sexual orientation, having undergone a tubal ligation, or remaining celibate by choice) who meets the following criteria: * Has not undergone a hysterectomy or bilateral oophorectomy; or …