Use of Endpoints in Phase III Randomized Controlled Trials for Hematopoietic Stem Cell Transplantation Over the Last 15 Years: A Systematic Review.

This systematic review aimed to evaluate the proportion of primary and secondary endpoints in hematopoietic stem cell transplant (HSCT) phase III randomized clinical trials (RCTs) and analyze their trends in time and study sponsorship status. The Chi-square test and logistic regression analyses were performed using SPSS version 28. A total of 147 HSCT phase III RCTs from 2006 to 2021 reported 197 primary and 600 secondary endpoints. Overall survival (OS, 17 %), progression-free survival (PFS, 15 %), graft versus host disease (GVHD, 8 %), event-free survival (EFS, 8 %), and organ function (8 %) were the most common primary endpoints. GVHD (12.3 %, n = 74), safety/toxicity/adverse events (11.8 %, n = 71), OS (11.5 %, n = 69), PFS (9.3 %, n = 56), and relapse rate (RR; 7.5 %, n = 45) were the most common secondary endpoints during 2006-2021. After 2013, an increase was noted in the use of PFS as a primary endpoint (12 %-18 %, p = 0.196), while the use of OS as a primary endpoint declined (20 %-13 %, p = 0.170). An increase was observed in using the secondary endpoints RR (5 %-10 %, p = 0.047) and NRM (3 %-6 %, p = 0.047). EFS was used more (14 % vs. 4 %, p = 0.012) than ORR (11 % vs. 2 %, p = 0.003) as a primary endpoint in pharmaceutical-compared to non-pharmaceutical-sponsored studies. As secondary endpoints, the use of EFS (4 % vs. 1 %, p = 0.013) and ORR (4 % vs. 1 %, p = 0.028) was higher, whereas that of organ systems/functions (1.5 % vs. 5.5 %, p = 0.022) and GVHD (6.5 % vs. 15 %, p = 0.002) was lower in pharmaceutical-compared to non-pharmaceutical sponsored studies. GVHD-free relapse-free survival was reported as a primary endpoint in 2 % of studies, while only 5 % reported quality of life as a secondary endpoint. We described commonly used endpoints in HSCT phase III RCTs and patterns in their use over time by funding source and study intervention category.

Predictors of cytomegalovirus reactivation after allogeneic hematopoietic cell transplantation: Insights from a real-world experience.

BACKGROUND: We aimed to investigate factors associated with cytomegalovirus (CMV) viremia and CMV disease and its impact on post-transplant outcomes including overall survival (OS) following allogeneic hematopoietic stem cell transplantation (Allo-SCT). METHODS: We conducted a single-center retrospective study including 452 Allo-SCT recipients (matched unrelated donor, MUD 61%; haploidentical, haplo 39%) from 2016 to 2021. Data were analyzed using SPSS v28. Descriptive (chi-square and t-test), Kaplan-Meier and regression analyses were conducted. RESULTS: The median age was 57 years. Sixty-one percent were males and 84.3% were Caucasians. CMV serostatus was positive in 59.1% of recipients. The median follow-up was 24.4 months. CMV viremia and CMV disease were observed in 181 (40%) and 32 (7%) patients, respectively. Among CMV seropositive recipients, 65% developed CMV viremia and 11% were noted to have CMV disease compared to 4% and 1% in seronegative recipients, respectively (p < 0.001). Patients with CMV disease had significantly lower OS than those without CMV disease (median 14.1 months vs. not reached, p = 0.024); however, OS was not associated with CMV viremia (median not reached in both groups, p = 0.640). Letermovir prophylaxis was used in 66% (n = 176/267) of CMV seropositive recipients, but no impact was observed on the incidence of CMV viremia or CMV disease and OS. CONCLUSIONS: CMV disease leads to significantly inferior survival after an allogeneic hematopoietic cell transplantation. Recipient CMV seropositive status was associated with the risk of CMV viremia and CMV disease, and this was not abrogated with the use of Letermovir prophylaxis.

Post hoc analysis of daratumumab plus lenalidomide, bortezomib and dexamethasone in Black patients from final data of the GRIFFIN study.

Due in part to racial disparities and underrepresentation in clinical studies, optimal therapies for Black patients with multiple myeloma remain undefined. This final analysis of GRIFFIN by race showed that the addition of daratumumab (D) to lenalidomide/bortezomib/dexamethasone (RVd) provides clinical benefit among both Black and White transplant-eligible newly diagnosed patients compared with RVd alone. However, Black patients were more likely to discontinue ≥1 drug due to treatment-emergent adverse events. In summary, these findings suggest a benefit of D-RVd front-line therapy among Black and White patients and underscore the importance of equitable treatment access for all patients.

Optimizing the CAR T-Cell Therapy Experience in Multiple Myeloma: Clinical Pearls From an Expert Roundtable.

Chimeric antigen receptor T-cell (CAR-T) therapies offer substantial advancement in the treatment of multiple myeloma (MM). However, the CAR-T therapy process involves complex decision-making that is informed by many variables. This review aims to provide an overview of the patient selection and administration process for CAR-T therapy for MM from the perspective of experienced healthcare providers (HCPs), including considerations for each step in the CAR-T therapy process. Referring HCPs should initiate conversations with HCPs at CAR-T capable centers earlier in the treatment journey, even before patients are eligible for CAR-T therapy, particularly for patients from underserved populations and patients with high-risk disease, to ensure adequate time for logistical planning and patient education. Patient selection for CAR-T therapy may be guided by factors such as performance status, rate of disease progression, and logistical considerations. Some anticancer therapies may affect T-cell fitness and therefore impact CAR-T manufacturing and patient outcomes; however, additional research is needed to confirm this in MM. Bridging therapies should be tailored to the needs of the patient and ideally halted 1 week or longer before CAR-T infusion, contingent upon the agent(s) used. Lymphodepletion regimens may need to be modified for patients with renal insufficiency. Collaboration with HCPs at both the treating and referring centers is important to optimize coordinated care of patients. Collaboration with and guidance from experienced HCPs throughout patient selection, referral, and CAR-T administration is instrumental in optimizing patient outcomes as access to CAR-T therapies expands.

Development and Validation of a Prediction Model of Outcome After B-Cell Maturation Antigen-Directed Chimeric Antigen Receptor T-Cell Therapy in Relapsed/Refractory Multiple Myeloma.

PURPOSE: Although chimeric antigen receptor T therapy (CAR-T) cells are an established therapy for relapsed/refractory multiple myeloma (RRMM), there are no established models predicting outcome to identify patients who may benefit the most from CAR-T. PATIENTS AND METHODS: This is an international retrospective observational study including patients with RRMM infused with currently available commercial or academically produced anti-B-cell maturation antigen (BCMA) CAR-T. We describe characteristics and outcomes in Europe (n = 136) and the United States (n = 133). Independent predictors of relapse/progression built a simple prediction model (Myeloma CAR-T Relapse [MyCARe] model) in the training cohort (Europe), which was externally validated (US cohort) and tested within patient- and treatment-specific subgroups. RESULTS: The overall response rate was 87% and comparable between both cohorts, and complete responses were seen in 48% (Europe) and 49% (the United States). The median time to relapse was 5 months, and early relapse <5 months from infusion showed poor survival across cohorts, with the 12-month overall survival of 30% (Europe) and 14% (the United States). The presence of extramedullary disease or plasma cell leukemia, lenalidomide-refractoriness, high-risk cytogenetics, and increased ferritin at the time of lymphodepletion were independent predictors of early relapse or progression. Each factor received one point, forming the three-tiered MyCARe model: scores 0-1 (low risk), scores 2-3 (intermediate risk), and a score of 4 (high risk). The MyCARe model was significantly associated with distinct 5-month incidence of relapse/progression (P < .001): 7% for low-risk, 27% for intermediate-risk, and 53% for high-risk groups. The model was validated in the US cohort and maintained prognostic utility for response, survival, and outcomes across subgroups. CONCLUSION: Outcomes of patients with RRMM after CAR-T are comparable between Europe and the United States. The MyCARe model may facilitate optimal timing of CAR-T cells in patient-specific subgroups.

Efficacy and safety of idecabtagene vicleucel in patients with relapsed-refractory multiple myeloma not meeting the KarMMa-1 trial eligibility criteria: A real-world multicentre study.

Ide-cel received approval for relapsed-refractory multiple myeloma based on the results of the KarMMa-1 trial. However, patients with significant comorbidities, aggressive disease and prior B-cell maturation antigen-directed therapy (BCMA-DT) were excluded. This retrospective study evaluated real-world outcomes of patients who did not meet the KarMMa-1 eligibility criteria and were treated with standard of care (SOC) ide-cel. A total of 69 patients from three US centres who did not meet the KarMMa-1 criteria underwent ide-cel infusion. The main reasons for trial ineligibility included baseline grade 3-4 cytopenia (39%), prior BCMA-DT (26%), renal impairment (19%) and Eastern Cooperative Oncology Group performance status ≥2 (14.5%). Cytokine-release syndrome occurred in 81% vs. 84%, and immune effector cell-associated neurotoxicity syndrome occurred in 28% vs. 18% of SOC versus KarMMa-1 patients, respectively. Early infection (≤8 weeks post-infusion) and severe infection rates were 42% vs. 49% and 30% vs. 22% for the SOC versus KarMMa-1 cohorts, respectively. Grade 3-4 cytopenias for SOC versus KarMMa-1 cohorts were: neutropenia (87% vs. 89%), anaemia (51% vs. 60%) and thrombocytopenia (65% vs. 52%). Overall response rate was higher for the SOC cohort (93% vs. 73%), as was the complete response or better rate (48% vs. 33%). However, median progression-free survival and overall survival were comparable between the two groups. Our findings support broadening the inclusion criteria of future trials evaluating ide-cel.

Outcomes with HLA-matched unrelated donor versus haploidentical hematopoietic cell transplantation.

We investigated the outcomes after adult haploidentical (haplo) and matched unrelated donor (MUD) hematopoietic cell transplantation (HCT) in a single-center study (n = 452) including 276 MUD and 176 haplo transplants. Myeloablative (37%) and reduced-intensity conditioning (63%) were performed. Graft sources included peripheral blood (50%) and bone marrow (50%). GVHD prophylaxis included tacrolimus/methotrexate (53%) and post-transplant cyclophosphamide-based (47%). In MUD versus haplo HCT recipients, a similar incidence of neutrophil engraftment (18 vs 17 days, p = 0.895), grade II-IV acute GVHD (51% vs 50%, p = 0.773), relapse (26% vs 23%, p = 0.578), non-relapse mortality (22% vs 23%, p = 0.817), 1-year disease-free survival (62% vs 63%. p = 0.921), and 1-year overall survival (73% vs 74%, p = 0.744) were observed. Earlier platelet engraftment (22 vs 27 days, p < 0.001) and higher chronic GVHD (45% vs 35%, p = 0.040) were noted in MUD as compared to haplo HCT. Allogeneic transplantation should be done promptly whenever indicated, utilizing either matched unrelated or haploidentical donors.

Five-year follow-up of a phase 2 study of ibrutinib plus fludarabine, cyclophosphamide, and rituximab as initial therapy in CLL.

ABSTRACT: We previously reported high rates of undetectable minimal residual disease <10-4 (uMRD4) with ibrutinib plus fludarabine, cyclophosphamide, and rituximab (iFCR) followed by 2-year ibrutinib maintenance (I-M) in treatment-naïve chronic lymphocytic leukemia (CLL). Here, we report updated data from this phase 2 study with a median follow-up of 63 months. Of 85 patients enrolled, including 5 (6%) with deletion 17p or TP53 mutation, 91% completed iFCR and 2-year I-M. Five-year progression-free survival (PFS) and overall survival were 94% (95% confidence interval [CI], 89%-100%) and 99% (95% CI, 96%-100%), respectively. No additional deaths have occurred with this extended follow-up. No difference in PFS was observed by immunoglobulin heavy-chain variable region gene status or duration of I-M. High rates of peripheral blood (PB) uMRD4 were maintained (72% at the end of iFCR, 66% at the end of 2-year I-M, and 44% at 4.5 years from treatment initiation). Thirteen patients developed MRD conversion without clinical progression, mostly (77%) after stopping ibrutinib. None had Bruton tyrosine kinase (BTK) mutations. One patient had PLCG2 mutation. Six of these patients underwent ibrutinib retreatment per protocol. Median time on ibrutinib retreatment was 34 months. The cumulative incidence of atrial fibrillation was 8%. Second malignancy or nonmalignant hematologic disease occurred in 13%, mostly nonmelanoma skin cancer. Overall, iFCR with 2-year I-M achieved durably deep responses in patients with diverse CLL genetic markers. Re-emergent clones lacked BTK mutation and retained sensitivity to ibrutinib upon retreatment. This trial is registered at www.clinicaltrials.gov as #NCT02251548.

Racial and ethnic differences in clinical outcomes among patients with multiple myeloma treated with CAR T-cell therapy.

ABSTRACT: Idecabtagene vicleucel (ide-cel) was the first chimeric antigen receptor T-cell therapy to gain US Food and Drug Administration approval for patients with relapsed/refractory multiple myeloma (RRMM). The clinical outcomes of standard of care (SOC) ide-cel in racially and ethnically diverse populations have been understudied. This study pooled data from 207 patients with RRMM (28% patients of racial and ethnic minority groups) treated with SOC ide-cel across 11 institutions to examine racial and ethnic differences in the incidence of toxicities and adverse events, response to ide-cel, and survival. This study included 22 (11%) Hispanic, 36 (17%) non-Hispanic Black, and 149 (72%) non-Hispanic White patients with RRMM. Compared with Hispanic and non-Hispanic White patients, non-Hispanic Black patients had higher median levels of C-reactive protein (1.0, 0.8, and 3.5 mg/dL, respectively; P = .02) and baseline ferritin (362.0 vs 307.0 vs 680.5, respectively; P = .08) and were more likely to develop cytokine release syndrome (77%, 85%, and 97%, respectively; P = .04). Although best overall response rate was lower among Hispanic patients (59%) than among non-Hispanic Black (86%) and White patients (86%; P = .01), there were no racial and ethnic differences in progression-free or overall survival. We provide, to our knowledge, the first and largest investigation of clinical outcomes of SOC ide-cel by race and ethnicity. Despite differences in safety and response to ide-cel, our findings encourage the use of ide-cel in all patients with RRMM. These findings should be confirmed in larger samples of diverse patients with RRMM, with longer follow-up time.

Idecabtagene vicleucel chimeric antigen receptor T-cell therapy for relapsed/refractory multiple myeloma with renal impairment.

We evaluated patients with relapsed multiple myeloma with renal impairment (RI) treated with standard of care idecabtagene vicleucel (ide-cel), as outcomes with chimeric antigen receptor (CAR) T-cell therapy are unknown in this population. RI was defined as creatinine clearance (CrCl) <50 mL/min. CrCl of <30 mL/min or dialysis dependence were defined as severe RI. The study cohort included 214 patients, 28 (13%) patients with RI, including 11 patients severe RI (dialysis, N=1). Patients with RI were older, more likely to be female and had higher likelihood of having Revised International Staging System stage 3 disease. Rates and severity of cytokine release syndrome (89% vs. 84%, grade ≥3: 7% vs. 2%) and immune effector cell-associated neurotoxicity syndrome (23% vs. 20%) were similar in patients with and without RI, respectively. Patients with RI had higher incidence of short-term grade ≥3 cytopenias, although cytopenias were similar by 3 months following CAR T-cell therapy. Renal function did not worsen after CAR T-cell therapy in patients with RI. Response rates (93% vs. 82%) and survival outcomes (median progression-free survival: 9 vs. 8 months; P=0.26) were comparable in patients with and without RI, respectively. Treatment with ide-cel is feasible in patients with RI, with a comparable safety and efficacy profile as patients without RI, with notable exception of higher short-term high-grade cytopenias.

Safety and Efficacy of Teclistamab in Patients with Relapsed/Refractory Multiple Myeloma: A Real-World Experience.

Teclistamab is a B cell maturation antigen (BCMA)-directed bispecific antibody approved for relapsed/refractory multiple myeloma (RRMM) on the basis of the phase I/II MajesTEC-1 trial. Here we report clinical outcomes with standard-of-care teclistamab in a real-world RRMM population. A total of 106 patients from 5 academic centers who received teclistamab from August 2022 to August 2023 were included in this retrospective analysis, 83% of whom would have been considered ineligible for the MajesTEC-1 trial. All patients were triple-class exposed, 64% were penta-class refractory, and 53% had received prior BCMA-directed therapy. Cytokine release syndrome was observed in 64% of patients, and only 1 event was grade ≥3, whereas immune effector cell-associated neurotoxicity syndrome was observed in 14% of patients (3 events were grade 3 or 4). One-third (31%) of patients experienced at least 1 infection, with nearly half of these infections graded as severe (grade ≥3). The overall response rate (ORR) was 66%, and the complete or better response rate was 29%. The ORR was 47% for patients with extramedullary disease (EMD), 59% for patients with prior BCMA-directed therapy exposure, and 68% for patients with penta-refractory disease. At a median follow-up of 3.8 months, the median progression-free survival (PFS) was 5.4 months (95% CI, 3.4 months to not reached), while median overall survival was not reached. Patients with Eastern Cooperative Oncology Group Performance Status ≥2, EMD, and age ≤70 years had inferior PFS on multivariable analysis. Our study demonstrates reasonable safety and good efficacy of teclistamab in patients with RRMM treated in a real-world setting.

Safety and efficacy of eltrombopag in patients with post-CAR T cytopenias.

BACKGROUND: While chimeric antigen receptor (CAR) T-cell therapy has revolutionized the treatment outcomes of relapsed/refractory hematological malignancies, this therapy is associated with post-treatment cytopenias, which can pose a challenge to its safe administration. This study describes the management of post-CAR T cytopenias using the thrombopoietin mimetic eltrombopag. METHODS: This retrospective analysis included adult patients with lymphoma or myeloma who received CAR T-cell therapy at two academic medical centers. Eltrombopag was initiated for patients who had persistent high-grade leukopenia and/or thrombocytopenia beyond 21 days post-CAR T infusion. Risk factors and outcomes were assessed and compared for patients who did or did not receive eltrombopag. RESULTS: Among the 185 patients analyzed, a majority (88%) experienced thrombocytopenia or leukopenia at day +30 post-CAR T infusion. A total of 42 patients met the criteria for eltrombopag treatment and initiated therapy. Patients who received eltrombopag were more likely to have pre-existing cytopenias at lymphodepletion, receive bridging therapy, experience an infection, or require intensive care. Recovery from cytopenias occurred within 180 days for a majority (94%) of patients. CONCLUSIONS: The use of eltrombopag for post-CAR T leukopenia and thrombocytopenia was considered safe without any significant toxicities. The use of eltrombopag for post-CAR T cytopenias might be effective in a high-risk patient population but requires further study.

Exploring the High-Grade and Refractory Neurotoxicity of Teclistamab: An Underreported Entity.

T-cell re-directing bispecific antibodies targeting B-cell maturation antigens have recently entered real-world use in relapsed/refractory multiple myeloma. While no head-to-head comparison has been done, they have generally been observed to have lower-grade toxicities compared with their chimeric antigen receptor T-cell (CAR-T) counterparts. However, in our real-world, single-institution experience, we have encountered two patients receiving teclistamab who experienced high-grade and refractory immune effector cell-associated neurotoxicity syndrome (ICANS) that did not respond to traditional toxicity mitigation strategies of high-dose corticosteroids or other immunosuppressive therapies. As we increase our use of these novel and vital agents, caution must be warranted.

Factors associated with refractoriness or early progression after idecabtagene vicleucel in patients with relapsed/refractory multiple myeloma: U.S. Myeloma Immunotherapy Consortium real world experience.

While response rates and survival outcomes have been very promising for idecabtagene vicleucel (ide-cel), a proportion of patients do not respond or relapse early after this B-cell maturation antigen (BCMA) targeted CAR T-cell therapy. Understanding the characteristics of these patients is important for patient selection and development of novel strategies to improve outcomes. We evaluated factors associated with early progression (progression or death due to myeloma ≤ 3 months after CAR T infusion) in patients treated with standard of care ide-cel at 11 US academic centers. Among 211 patients that received ide-cel, 43 patients had a progressive event ≤ 3 months of infusion. Patients with a history of extramedullary disease, prior BCMA targeted therapy, elevated ferritin at lymphodepletion, use of bridging therapy, Hispanic ethnicity, plasma cell leukemia and t(4;14) were more likely to progress ≤ 3 months of infusion (p < 0.05). Of these risk factors for early progression identified in univariate analyses, history of extramedullary disease, prior BCMA targeted therapy, elevated ferritin at lymphodepletion, plasma cell leukemia, and t(4;14) were associated with worse progression-free survival (PFS) in multivariable analysis. Presence of three or more of these factors had a significant negative impact on PFS (p < 0.001; median PFS for ≥ 3 factors, 3.2 months vs. 0 factors, 14.1 months). This study helps identify patients at high risk of early progression after CAR T who may benefit from specific interventions pre and post CAR T to improve outcomes.

Real-world experience of patients with multiple myeloma receiving ide-cel after a prior BCMA-targeted therapy.

Most patients with multiple myeloma experience disease relapse after treatment with a B-cell maturation antigen-targeted therapy (BCMA-TT), and data describing outcomes for patients treated with sequential BCMA-TT are limited. We analyzed clinical outcomes for patients infused with standard-of-care idecabtagene vicleucel, an anti-BCMA chimeric antigen receptor (CAR) T-cell therapy, at 11 US medical centers. A total of 50 patients with prior BCMA-TT exposure (38 antibody-drug conjugate, 7 bispecific, 5 CAR T) and 153 patients with no prior BCMA-TT were infused with ide-cel, with a median follow-up duration of 4.5 and 6.0 months, respectively. Safety outcomes between cohorts were comparable. The prior BCMA-TT cohort had a lower overall response rate (74% versus 88%; p = 0.021), median duration of response (7.4 versus 9.6 months; p = 0.03), and median progression-free survival (3.2 months versus 9.0 months; p = 0.0002) compared to the cohort without prior BCMA-TT. All five patients who received a prior anti-BCMA CAR T responded to ide-cel, and survival outcomes were best for this subgroup. In conclusion, treatment with ide-cel yielded meaningful clinical responses in real-world patients exposed to a prior BCMA-TT, though response rates and durability were suboptimal compared to those not treated with a prior BCMA-TT.

Lessons learned from COVID-19 pandemic: outcomes after SARS-CoV-2 infection in hematopoietic cell transplant and cell therapy recipients.

We investigated the outcomes after Coronavirus disease 2019 (COVID) in hematopoietic cell transplant (HCT) or chimeric antigen receptor-T cell (CART) therapy recipients in a single-centre study including all (n = 261)HCT/CART recipients (allogeneic-HCT 49%, autologous-HCT 40%, CART 11%). The median age was 60 (22-80) years. COVID severity was mild (74%), moderate (11%), and severe/critical (16%) with a mortality rate of 7% and a median duration of infection of 5.7 weeks. Significant predictors of COVID severe disease or mortality included concurrent infection (HR 14.9, 95% CI 2.2-5.6) and immunosuppressive therapy (OR 4.8, 95% CI 1.2-3.4).HCT/CART recipients have a higher risk of mortality with COVID and warrant vigilant interventions.

"Waitlist mortality" is high for myeloma patients with limited access to BCMA therapy.

Background: The first-in-class approved BCMA CAR-T therapy was idecabtagene vicleucel (ide-cel), approved in March 2021, for RRMM patients who progressed after 4 or more lines of therapy. Despite the promising outcomes, there were limited apheresis/production slots for ide-cel. We report outcomes of patients at our institution who were on the "waitlist" to receive ide-cel in 2021 and who could not secure a slot. Methods: We conducted a retrospective review of RRMM patients evaluated at the University of Kansas Cancer Center for ide-cel from 3/2021-7/2021. A retrospective chart review was performed to determine patient and disease characteristics. Descriptive statistics were reported using medians for continuous variables. Survival analysis from initial consult was performed using Kaplan-Meier Survival estimator. Results: Forty patients were eligible and were on the "waitlist" for CAR-T. The median follow-up was 14 months (2-25mo). Twenty-four patients (60%) secured a production slot and 16 (40%) did not. The median time from consult to collection was 38 days (8-703). The median time from collection to infusion was 42 days (34-132 days). The median overall survival was higher in the CAR-T group (NR vs 9 mo, p<0.001). Conclusions: Many patients who were eligible for ide-cel were not able to secure a timely slot in 2021. Mortality was higher in this group, due to a lack of comparable alternatives. Increasing alternate options as well as improvement in manufacturing and access is an area of high importance to improve RRMM outcomes.

Targeted therapy with nanatinostat and valganciclovir in recurrent EBV-positive lymphoid malignancies: a phase 1b/2 study.

Lymphomas are not infrequently associated with the Epstein-Barr virus (EBV), and EBV positivity is linked to worse outcomes in several subtypes. Nanatinostat is a class-I selective oral histone deacetylase inhibitor that induces the expression of lytic EBV BGLF4 protein kinase in EBV+ tumor cells, activating ganciclovir via phosphorylation, resulting in tumor cell apoptosis. This phase 1b/2 study investigated the combination of nanatinostat with valganciclovir in patients aged ≥18 years with EBV+ lymphomas relapsed/refractory to ≥1 prior systemic therapy with no viable curative treatment options. In the phase 1b part, 25 patients were enrolled into 5 dose escalation cohorts to determine the recommended phase 2 dose (RP2D) for phase 2 expansion. Phase 2 patients (n = 30) received RP2D (nanatinostat 20 mg daily, 4 days per week with valganciclovir 900 mg orally daily) for 28-day cycles. The primary end points were safety, RP2D determination (phase 1b), and overall response rate (ORR; phase 2). Overall, 55 patients were enrolled (B-non-Hodgkin lymphoma [B-NHL], [n = 10]; angioimmunoblastic T-cell lymphoma-NHL, [n = 21]; classical Hodgkin lymphoma, [n = 11]; and immunodeficiency-associated lymphoproliferative disorders, [n = 13]). The ORR was 40% in 43 evaluable patients (complete response rate [CRR], 19% [n = 8]) with a median duration of response of 10.4 months. For angioimmunoblastic T-cell lymphoma-NHL (n = 15; all refractory to the last prior therapy), the ORR/CRR ratio was 60%/27%. The most common adverse events were nausea (38% any grade) and cytopenia (grade 3/4 neutropenia [29%], thrombocytopenia [20%], and anemia [20%]). This novel oral regimen provided encouraging efficacy across several EBV+ lymphoma subtypes and warrants further evaluation; a confirmatory phase 2 study (NCT05011058) is underway. This phase 1b/2 study is registered at www.clinicaltrials.gov as #NCT03397706.