Tremelimumab (CP-675,206): a fully human anticytotoxic T lymphocyte-associated antigen 4 monoclonal antibody for treatment of patients with advanced cancers

Durvalumab after Chemoradiotherapy in Limited-Stage Small-Cell Lung Cancer

BACKGROUND

Adjuvant therapy with durvalumab, with or without tremelimumab, may have efficacy in patients with limited-stage small-cell lung cancer who do not have disease progression after standard concurrent platinum-based chemoradiotherapy.

METHODS

In a phase 3, double-blind, randomized, placebo-controlled trial, we assigned patients to receive durvalumab at a dose of 1500 mg, durvalumab (1500 mg) plus tremelimumab at a dose of 75 mg (four doses only), or placebo every 4 weeks for up to 24 months. Randomization was stratified according to disease stage (I or II vs. III) and receipt of prophylactic cranial irradiation (yes vs. no). Results of the first planned interim analysis of the two primary end points of overall survival and progression-free survival (assessed on the basis of blinded independent central review according to the Response Evaluation Criteria in Solid Tumors, version 1.1) with durvalumab as compared with placebo (data cutoff date, January 15, 2024) are reported; results in the durvalumab-tremelimumab group remain blinded.

RESULTS

A total of 264 patients were assigned to the durvalumab group, 200 to the durvalumab-tremelimumab group, and 266 to the placebo group. Durvalumab therapy led to significantly longer overall survival than placebo (median, 55.9 months [95% confidence interval {CI}, 37.3 to not reached] vs. 33.4 months [95% CI, 25.5 to 39.9]; hazard ratio for death, 0.73; 98.321% CI, 0.54 to 0.98; P = 0.01), as well as to significantly longer progression-free survival (median 16.6 months [95% CI, 10.2 to 28.2] vs. 9.2 months [95% CI, 7.4 to 12.9]; hazard ratio for progression or death, 0.76; 97.195% CI, 0.59 to 0.98; P = 0.02). The incidence of adverse events with a maximum grade of 3 or 4 was 24.4% among patients receiving durvalumab and 24.2% among patients receiving placebo; adverse events led to discontinuation in 16.4% and 10.6% of the patients, respectively, and led to death in 2.7% and 1.9%. Pneumonitis or radiation pneumonitis with a maximum grade of 3 or 4 occurred in 3.1% of the patients in the durvalumab group and in 2.6% of those in the placebo group.

CONCLUSIONS

Adjuvant therapy with durvalumab led to significantly longer overall survival and progression-free survival than placebo among patients with limited-stage small-cell lung cancer. (Funded by AstraZeneca; ADRIATIC ClinicalTrials.gov number, NCT03703297.).

The frontier of neoadjuvant therapy in non-small cell lung cancer beyond PD-(L)1 agents

INTRODUCTION

While surgical resection is the cornerstone of treatment for resectable lung cancer, neoadjuvant/adjuvant chemotherapy has shown limited improvement in survival rates over the past decades. With the success of immune checkpoint inhibitors (ICIs) in advanced NSCLC, there is growing interest in their application in earlier stages of the disease. Recent approvals for neoadjuvant/adjuvant ICIs in stage II-IIIA NSCLC highlight this shift in treatment paradigms.

AREAS COVERED

In this review, we aim to explore available data regarding alternative agents beyond the PD-(L)1 inhibitors, such as monoclonal antibodies against CTLA4, LAG3, TIGIT, antiangiogenic drugs, and novel therapies (antibody drug conjugates, bispecific antibodies) in neoadjuvant/perioperative regimens.

EXPERT OPINION

Novel agents and combinations (with or without ICI or/and chemotherapy), guided by molecular profiling and immune phenotyping, showed promise in improving surgical and survival outcomes. Crucial is, also in early setting, to identifying biomarkers predictive of treatment efficacy in order to personalize neoadjuvant/perioperative treatment strategies.

A meta-analysis of the efficacy of programmed cell death 1/its ligand inhibitors plus cytotoxic T-lymphocyte-associated antigen 4 inhibitors in non-small cell lung cancer

Background: Immune checkpoint inhibitors (ICIs), either as monotherapy or in combination with chemotherapy, have improved the therapeutic outcome for non-small cell lung cancer (NSCLC). However, the efficacy of combination therapies, such as programmed cell death 1(PD-1)/its ligand (PD-L1) and cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) inhibitors, in targeting different pathways remains unclear. We performed a meta-analysis to determine whether the addition of a CTLA-4 inhibitor to PD-1/PD-L1 therapy improves the efficacy of PD-1/PD-L1 monotherapy in NSCLC. Methods: We systematically searched various electronic databases for suitable trials. Only randomized controlled trials (RCTs) comparing the clinical efficacy of PD-1/PD-L1 with and without CTLA-4 were included in the analyses. The meta-analysis software RevMan 5.3 was used for statistical analyses. Results: A total of seven RCTs were retrieved. The results suggested that the combination of CTLA-4 and PD-1/PDL-1 inhibitors did not show enhanced efficacy over PD1/PDL-1 inhibitor monotherapy as determined by overall survival (OS) (HR = 0.98, 95% CI = 0.84-1.14, p = 0.79), progression-free survival (PFS) (HR = 0.92, 95% CI = 0.81-1.06, p = 0.25), and objective response rate (ORR) (HR = 1.08, 95% CI = 0.96-1.21, p = 0.19). Furthermore, the combination immunotherapy was associated increased toxicity as evidenced by increased incidence of any type adverse events (AEs) (RR = 1.06, 95% CI = 1.00-1.13, p = 0.03), grade ≥3 immune-mediated AEs (RR = 1.58, 95% CI = 1.36-1.82, p < 0.05), and treatment discontinuation (RR = 1.83, 95% CI = 1.46-2.28, p < 0.05). Conclusion: Combining anti-CTLA-4 with anti-PD-1/PD-L1 therapy did not improve the therapeutic efficacy, and was associated with greater toxicity than anti-PD-1/PD-L1 monotherapy in patients with advanced NSCLC. Further investigation of the combination immunotherapy in specific subsets of patients is warranted to identify and define the patient-specific benefits of this combination. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42023435399.

Patient-reported outcomes with durvalumab, with or without tremelimumab, plus chemotherapy as first-line treatment for metastatic non-small-cell lung cancer (POSEIDON)

OBJECTIVES

In the phase 3 POSEIDON study, first-line tremelimumab plus durvalumab and chemotherapy significantly improved overall survival and progression-free survival versus chemotherapy in metastatic non-small-cell lung cancer (NSCLC). We present patient-reported outcomes (PROs).

PATIENTS AND METHODS

Treatment-naïve patients were randomized 1:1:1 to tremelimumab plus durvalumab and chemotherapy, durvalumab plus chemotherapy, or chemotherapy. PROs (prespecified secondary endpoints) were assessed using the European Organisation for Research and Treatment of Cancer 30-item core quality of life questionnaire version 3 (QLQ-C30) and its 13-item lung cancer module (QLQ-LC13). We analyzed time to deterioration (TTD) of symptoms, functioning, and global health status/quality of life (QoL) from randomization by log-rank test and improvement rates by logistic regression.

RESULTS

972/1013 (96 %) patients randomized completed baseline QLQ-C30 and QLQ-LC13 questionnaires, with scores comparable between treatment arms. Patients receiving tremelimumab plus durvalumab and chemotherapy versus chemotherapy had longer median TTD for all PRO items. Hazard ratios for TTD favored tremelimumab plus durvalumab and chemotherapy for all items except diarrhea; 95 % confidence intervals did not cross 1.0 for global health status/QoL, physical functioning, cognitive functioning, pain, nausea/vomiting, insomnia, constipation, hemoptysis, dyspnea, and pain in other parts. For durvalumab plus chemotherapy, median TTD was longer versus chemotherapy for all items except nausea/vomiting and diarrhea. Hazard ratios favored durvalumab plus chemotherapy for all items except appetite loss; 95 % confidence intervals did not cross 1.0 for global health status/QoL, physical functioning, role functioning, dyspnea, and pain in other parts. For both immunotherapy plus chemotherapy arms, improvement rates in all PRO items were numerically higher versus chemotherapy, with odds ratios > 1.

CONCLUSIONS

Tremelimumab plus durvalumab and chemotherapy delayed deterioration in symptoms, functioning, and global health status/QoL compared with chemotherapy. Together with significant improvements in survival, these results support tremelimumab plus durvalumab and chemotherapy as a first-line treatment option in metastatic NSCLC.

Phase II Trial of Combined Durvalumab Plus Tremelimumab with Proton Therapy for Recurrent or Metastatic Head and Neck Squamous Cell Carcinoma

PURPOSE

This phase II study investigated whether durvalumab/tremelimumab with proton therapy improves the objective response rate (ORR), overall survival (OS), and progression-free survival (PFS) in heavily treated recurrent or metastatic head and neck squamous cell carcinoma (HNSCC) patients.

MATERIALS AND METHODS

Patients who previously received more than one chemotherapy, including at least one platinum-based regimen, and who had at least two measurable lesions were enrolled. Patients received 1,500 mg durvalumab intravenously combined with 75 mg tremelimumab intravenously every 4 weeks for four cycles followed by 1,500 mg durvalumab every 4 weeks. After one cycle of the durvalumab/tremelimumab treatment, proton therapy was given with a total dose of 25 Gy in 5 Gy daily fractions to one of the measurable lesions. We also assessed the ORR in the target lesion outside the radiation field to evaluate the abscopal effect.

RESULTS

Thirty-one patients were enrolled between March 2018 and July 2020. With 8.6 months of follow-up, the ORR was 22.6% (7/31), including one complete response and six partial responses. The median OS was 8.4 months (95% confidence interval [CI], 2.5 to 14.3) and the median PFS was 2.4 months (95% CI, 0.6 to 4.2). Among the 23 evaluable patients who completed proton therapy, the ORR was 30.4% (7/23). The median OS was 11.1 months (95% CI, 6.5 to 15.8), and the median PFS was 3.7 months (95% CI, 1.6 to 5.7). Grade 3 or higher adverse events were observed in six patients (19.4%) as follows: anemia (n=1), constipation (n=1), electrolyte imbalances (n=2), hyperglycemia (n=1), and pneumonia (n=1).

CONCLUSION

The combination of durvalumab/tremelimuab with proton therapy was tolerated well and had encouraging anti-tumor efficacy in non-irradiated tumor lesions of heavily treated HNSCC patients.

Recent advances in non-small cell lung cancer targeted therapy; an update review

Lung cancer continues to be the leading cause of cancer-related death worldwide. In the last decade, significant advancements in the diagnosis and treatment of lung cancer, particularly NSCLC, have been achieved with the help of molecular translational research. Among the hopeful breakthroughs in therapeutic approaches, advances in targeted therapy have brought the most successful outcomes in NSCLC treatment. In targeted therapy, antagonists target the specific genes, proteins, or the microenvironment of tumors supporting cancer growth and survival. Indeed, cancer can be managed by blocking the target genes related to tumor cell progression without causing noticeable damage to normal cells. Currently, efforts have been focused on improving the targeted therapy aspects regarding the encouraging outcomes in cancer treatment and the quality of life of patients. Treatment with targeted therapy for NSCLC is changing rapidly due to the pace of scientific research. Accordingly, this updated study aimed to discuss the tumor target antigens comprehensively and targeted therapy-related agents in NSCLC. The current study also summarized the available clinical trial studies for NSCLC patients.

First-line tremelimumab plus durvalumab and chemotherapy versus chemotherapy alone for metastatic non-small cell lung cancer: a cost-effectiveness analysis in the United States

Importance: In the open-label phase III POSEIDON randomized clinical trial (RCT), a limited course of tremelimumab plus durvalumab and chemotherapy (T + D + CT) indicated in the first-line treatment of metastatic non-small cell lung cancer (mNSCLC), progression-free survival, and overall survival (OS) were substantially improved without significant additional tolerance burden compared to chemotherapy (CT). However, given the high cost of T + D + CT, its value needs to be evaluated in terms of both potency and cost. Objective: To evaluate the cost-effectiveness of T + D + CT versus CT in individuals with previously untreated mNSCLC from a U.S. payer perspective. Design, setting, and participants: A three-state Markov model was adopted to weigh the lifetime costs and effectiveness of T + D + CT versus CT for the treatment of first-line mNSCLC, according to the results of the POSEIDON phase III RCT involving 675 individuals with mNSCLC. Individuals were simulated to undergo either T + D + CT for up to four 21-day cycles, followed by durvalumab once every 4 weeks until disease progression or unacceptable toxic effects and one additional tremelimumab dose, or CT for up to six 21-day cycles (with or without pemetrexed maintenance; all groups) in the analysis. Main outcomes and measures: Lifetime costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratio (ICER) were evaluated with a willingness-to-pay (WTP) threshold of $ 100,000 to $ 150,000 per QALY. The uncertainty of the model was investigated using univariate and probabilistic sensitivity analysis. Results: T + D + CT produced additional 0.36 QALYs with additional costs of $ 217,694, compared to CT, giving rise to ICERs of $ 608,667.86/QALY. The univariate sensitivity analysis demonstrated that the outcomes were most sensitive to the cost of durvalumab. Other variables with a large or moderate influence were the utility of progression-free survival state, utility of progressive disease state, and cost of tremelimumab. Probability sensitivity analysis revealed that T + D + CT had a 0% probability of cost-effectiveness in individuals with mNSCLC at a willingness-to-pay threshold of $ 100,000 to $ 150,000 per QALY. Conclusion and relevance: In this model, T + D + CT was estimated to be less cost-effective than CT for patients with mNSCLC at a WTP threshold of $ 100,000 to $ 150,000 per QALY in the United States. When new combination therapies with remarkable effect become pivotal in the first-line treatment, the price reduction of durvalumab and tremelimumab may be necessary to achieve cost-effectiveness in future possible context.

Immunotherapy for recurrent hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is presented frequently in late stages that are not amenable for curative treatment. Even for patients who can undergo resection for curative treatment of HCC, up to 50% recur. For patients who were not exposed to systemic therapy prior to recurrence, recurrence frequently cannot be subjected to curative therapy or local treatments. Such patients have several options of immunotherapy (IO). This includes programmed cell death protein 1 (PD-1) and cytotoxic T- lymphocyte associated protein 4 treatment, combination of PD-1 and vascular endothelial growth factor inhibitor or single agent PD-1 therapy when all other options are deemed inappropriate. There are also investigational therapies in this area that explore either PD-1 and tyrosine kinase inhibitors or a novel agent in addition to PD-1 with vascular endothelial growth factor inhibitors. This mini-review explored IO options for patients with recurrent HCC who were not exposed to systemic therapy at the initial diagnosis. We also discussed potential IO options for patients with recurrent HCC who were exposed to first-line therapy with curative intent at diagnosis.

What Is New in Small Cell Lung Cancer

Small cell lung cancer (SCLC) is a rare yet aggressive lung cancer subtype with an extremely poor prognosis of around 1 year. SCLC accounts for 15% of all newly diagnosed lung cancers and is characterized by rapid growth with high potential for metastatic spread and treatment resistance. In the article the authors review some of the most notable efforts to improve outcomes, including trials of novel immunotherapy agents, novel disease targets, and multiple drug combinations.

Durvalumab With or Without Tremelimumab in Combination With Chemotherapy as First-Line Therapy for Metastatic Non-Small-Cell Lung Cancer: The Phase III POSEIDON Study

PURPOSE

The open-label, phase III POSEIDON study evaluated tremelimumab plus durvalumab and chemotherapy (T + D + CT) and durvalumab plus chemotherapy (D + CT) versus chemotherapy alone (CT) in first-line metastatic non-small-cell lung cancer (mNSCLC).

METHODS

Patients (n = 1,013) with EGFR/ALK wild-type mNSCLC were randomly assigned (1:1:1) to tremelimumab 75 mg plus durvalumab 1,500 mg and platinum-based chemotherapy for up to four 21-day cycles, followed by durvalumab once every 4 weeks until progression and one additional tremelimumab dose; durvalumab plus chemotherapy for up to four 21-day cycles, followed by durvalumab once every 4 weeks until progression; or chemotherapy for up to six 21-day cycles (with or without maintenance pemetrexed; all arms). Primary end points were progression-free survival (PFS) and overall survival (OS) for D + CT versus CT. Key alpha-controlled secondary end points were PFS and OS for T + D + CT versus CT.

RESULTS

PFS was significantly improved with D + CT versus CT (hazard ratio [HR], 0.74; 95% CI, 0.62 to 0.89; P = .0009; median, 5.5 v 4.8 months); a trend for improved OS did not reach statistical significance (HR, 0.86; 95% CI, 0.72 to 1.02; P = .0758; median, 13.3 v 11.7 months; 24-month OS, 29.6% v 22.1%). PFS (HR, 0.72; 95% CI, 0.60 to 0.86; P = .0003; median, 6.2 v 4.8 months) and OS (HR, 0.77; 95% CI, 0.65 to 0.92; P = .0030; median, 14.0 v 11.7 months; 24-month OS, 32.9% v 22.1%) were significantly improved with T + D + CT versus CT. Treatment-related adverse events were maximum grade 3/4 in 51.8%, 44.6%, and 44.4% of patients receiving T + D + CT, D + CT, and CT, respectively; 15.5%, 14.1%, and 9.9%, respectively, discontinued treatment because of treatment-related adverse events.

CONCLUSION

D + CT significantly improved PFS versus CT. A limited course of tremelimumab added to durvalumab and chemotherapy significantly improved OS and PFS versus CT, without meaningful additional tolerability burden, representing a potential new option in first-line mNSCLC.

NEPTUNE China cohort: First-line durvalumab plus tremelimumab in Chinese patients with metastatic non-small-cell lung cancer

OBJECTIVES

The phase 3 NEPTUNE study (NCT02542293) evaluated first-line durvalumab plus tremelimumab (DT) versus chemotherapy for metastatic NSCLC. Prespecified exploratory analyses were conducted in an extended cohort enrolled in China.

MATERIALS AND METHODS

Patients were randomized (1:1) to DT or standard chemotherapy, stratified by PD-L1 tumor cell (TC) expression (≥25 % vs < 25 %), histology, and smoking history. The primary analysis for this cohort was overall survival (OS) in patients with PD-L1 TC < 1 %. Secondary analyses included OS and progression-free survival (PFS) in the ITT population and PD-L1 subgroups, and safety. No alpha was allocated to these cohort analyses (data cut-off, 21-September-2020).

RESULTS

78 and 82 patients were randomized to DT and chemotherapy, respectively; 26 and 29 had PD-L1 TC < 1 % (median follow-up, 31.2 and 29.7 months [censored patients]). Among patients with PD-L1 TC < 1 %, OS favored DT versus chemotherapy (HR 0.60; 95 % CI, 0.32-1.11), with medians of 15.0 months (95 % CI, 10.5-27.4) and 11.7 months (95 % CI, 8.6-20.5), respectively; 24-month rates were 36.0 % (95 % CI, 18.2-54.2) and 17.9 % (95 % CI, 6.5-33.7). In the ITT population, OS was prolonged with DT versus chemotherapy (HR 0.70; 95 % CI, 0.48-1.02); medians were 20.0 and 14.1 months and 24-month rates were 44.2 % and 30.4 %. PFS was similar in the PD-L1 TC < 1 % (HR 1.13; 95 % CI, 0.59-2.14) and ITT (HR 0.95; 95 % CI, 0.66-1.36) populations; 12-month rates were 15.6 % versus 11.3 % and 23.9 % versus 16.6 %. Grade 3/4 treatment-related adverse events (TRAEs) occurred in 31.2 % with DT and 52.6 % with chemotherapy; 3.9 % versus 10.3 % discontinued due to TRAEs.

CONCLUSIONS

In exploratory analyses, first-line DT showed a trend towards improved OS versus chemotherapy among Chinese patients in the PD-L1 TC < 1 % population and ITT population, with 24-month OS and 12-month PFS rates indicating benefit in survival curve tails. DT was well tolerated with no new safety signals.

Durvalumab with or without tremelimumab combined with particle therapy for advanced hepatocellular carcinoma with macrovascular invasion: protocol for the DEPARTURE phase Ib trial

INTRODUCTION

Advanced hepatocellular carcinoma (HCC) with macrovascular invasion (MVI) has the worst prognosis among all phenotypes. This trial aims to evaluate whether treatment with durvalumab, alone or in combination with tremelimumab, plus particle therapy is a safe and synergistically effective treatment in patients with advanced HCC and MVI.

METHODS AND ANALYSIS

This phase Ib, multicentre (two sites in Japan), open-label, single-arm, investigator-initiated clinical trial will assess durvalumab monotherapy in combination with particle therapy (cohort A) and that of durvalumab plus tremelimumab in combination with particle therapy (cohort B) for patients with advanced HCC with MVI. Cohort A will receive 1500 mg durvalumab every 4 weeks. Cohort B will receive 1500 mg durvalumab every 4 weeks in principle and 300 mg tremelimumab only on day 1 of the first cycle. Carbon-ion radiotherapy will be administered after day 8 of the first cycle. The primary endpoints are rates of any and severe adverse events, including dose-limiting toxicities (DLTs); secondary endpoints are overall survival, 6-month survival, objective response, 6-month progression-free survival and time to progression. Patients are initially enrolled into cohort A. If cohort A treatment is confirmed to be tolerated (ie, no DLT in three patients or one DLT in six patients), the trial proceeds to enrol more patients into cohort B. Similarly, if cohort B treatment is confirmed to be tolerated (ie, no DLT in three patients or one DLT in six patients), a total of 15 patients will be enrolled into cohort B.

ETHICS AND DISSEMINATION

This study was approved by the ethics committees of the two participating institutions (Chiba University Hospital and National Institutes for Quantum (approval number: 2020040) and Radiological Science and Technology, QST Hospital (approval number: C20-001)). Participants will be required to provide written informed consent. Trial results will be reported in a peer-reviewed journal publication.

TRIAL REGISTRATION NUMBER

jRCT2031210046.

Results from a Meta-analysis of Combination of PD-1/PD-L1 and CTLA-4 Inhibitors in Malignant Cancer Patients: Does PD-L1 Matter?

Background: Combination therapy with immune checkpoint inhibitors (ICIs) has been widely used for clinical treatment in recent years, which has a better survival benefit. However, not all patients can derive clinical benefit from combination immunotherapy. Therefore, it is necessary to explore the biomarkers of combination immunotherapy.

Methods: We retrieved articles from electronic databases including PubMed, EMBASE and Cochrane. The statistical analysis was performed using RevMan software. Progression free survival (PFS), overall survival (OS) and objective response rate (ORR) were the outcome indicators. In the unselect population, we compared combination therapy with other treatments. In addition, we also conducted subgroup analysis on PFS, OS and ORR according to PD-L1 status.

Results: Seven studies were included in the analysis for a total of 3,515 cases. In the unselected population, we found that combination therapy has longer PFS, OS, and better ORR than other treatments for cancer patients. The longer PFS was showed in PD-L1 ≥ 5% cases (HR = 0.64, 95% CI: 0.56–0.76; p < 0.001) than PD-L1 ≥ 1% cases (HR = 0.72, 95% CI: 0.66–0.79; p < 0.001), while ORR and OS have not related to the status of PD-L1.

Conclusion: This study supported the efficacy of combination therapy with immune checkpoint inhibitors (ICIs), and also showed that PFS in patients with malignant tumors is positively correlated with PD-L1 expression. Due to the limited number of trials included, more high-quality clinical randomized controlled trials should be conducted to confirm the review findings.

Recent Advances in Monoclonal Antibody Therapy for Colorectal Cancers

Colorectal cancer (CRC) is one of the leading causes of cancer deaths worldwide. Recent advances in recombinant DNA technology have led to the development of numerous therapeutic antibodies as major sources of blockbuster drugs for CRC therapy. Simultaneously, increasing numbers of therapeutic targets in CRC have been identified. In this review, we first highlight the physiological and pathophysiological roles and signaling mechanisms of currently known and emerging therapeutic targets, including growth factors and their receptors as well as immune checkpoint proteins, in CRC. Additionally, we discuss the current status of monoclonal antibodies in clinical development and approved by US Food and Drug Administration for CRC therapy.

Durvalumab With or Without Tremelimumab vs Standard Chemotherapy in First-line Treatment of Metastatic Non-Small Cell Lung Cancer: The MYSTIC Phase 3 Randomized Clinical Trial

Question

Does first-line durvalumab treatment with or without tremelimumab improve survival outcomes vs chemotherapy in patients with metastatic non–small cell lung cancer?

Findings

In this phase 3 randomized clinical trial including 1118 patients with non–small cell lung cancer, although the trial did not meet its primary end points, treatment with durvalumab resulted in a numerically reduced risk of death vs chemotherapy in patients with programmed cell death ligand 1 expression on at least 25% of tumor cells. In exploratory analyses, a blood tumor mutational burden threshold of at least 20 mutations per megabase was identified for optimal clinical benefit with durvalumab plus tremelimumab vs chemotherapy.

Meaning

These findings highlight the need for further investigation and prospective validation of blood tumor mutational burden as a predictive biomarker for immunotherapy.

Importance

Checkpoint inhibitors targeting programmed cell death 1 or its ligand (PD-L1) as monotherapies or in combination with anti–cytotoxic T-lymphocyte–associated antigen 4 have shown clinical activity in patients with metastatic non–small cell lung cancer.

Objective

To compare durvalumab, with or without tremelimumab, with chemotherapy as a first-line treatment for patients with metastatic non–small cell lung cancer.

Design, Setting, and Participants

This open-label, phase 3 randomized clinical trial (MYSTIC) was conducted at 203 cancer treatment centers in 17 countries. Patients with treatment-naive, metastatic non–small cell lung cancer who had no sensitizing EGFR or ALK genetic alterations were randomized to receive treatment with durvalumab, durvalumab plus tremelimumab, or chemotherapy. Data were collected from July 21, 2015, to October 30, 2018.

Interventions

Patients were randomized (1:1:1) to receive treatment with durvalumab (20 mg/kg every 4 weeks), durvalumab (20 mg/kg every 4 weeks) plus tremelimumab (1 mg/kg every 4 weeks, up to 4 doses), or platinum-based doublet chemotherapy.

Main Outcomes and Measures

The primary end points, assessed in patients with ≥25% of tumor cells expressing PD-L1, were overall survival (OS) for durvalumab vs chemotherapy, and OS and progression-free survival (PFS) for durvalumab plus tremelimumab vs chemotherapy. Analysis of blood tumor mutational burden (bTMB) was exploratory.

Results

Between July 21, 2015, and June 8, 2016, 1118 patients were randomized. Baseline demographic and disease characteristics were balanced between treatment groups. Among 488 patients with ≥25% of tumor cells expressing PD-L1, median OS was 16.3 months (95% CI, 12.2-20.8) with durvalumab vs 12.9 months (95% CI, 10.5-15.0) with chemotherapy (hazard ratio [HR], 0.76; 97.54% CI, 0.56-1.02; P = .04 [nonsignificant]). Median OS was 11.9 months (95% CI, 9.0-17.7) with durvalumab plus tremelimumab (HR vs chemotherapy, 0.85; 98.77% CI, 0.61-1.17; P = .20). Median PFS was 3.9 months (95% CI, 2.8-5.0) with durvalumab plus tremelimumab vs 5.4 months (95% CI, 4.6-5.8) with chemotherapy (HR, 1.05; 99.5% CI, 0.72-1.53; P = .71). Among 809 patients with evaluable bTMB, those with a bTMB ≥20 mutations per megabase showed improved OS for durvalumab plus tremelimumab vs chemotherapy (median OS, 21.9 months [95% CI, 11.4-32.8] vs 10.0 months [95% CI, 8.1-11.7]; HR, 0.49; 95% CI, 0.32-0.74). Treatment-related adverse events of grade 3 or higher occurred in 55 (14.9%) of 369 patients who received treatment with durvalumab, 85 (22.9%) of 371 patients who received treatment with durvalumab plus tremelimumab, and 119 (33.8%) of 352 patients who received treatment with chemotherapy. These adverse events led to death in 2 (0.5%), 6 (1.6%), and 3 (0.9%) patients, respectively.

Conclusions and Relevance

The phase 3 MYSTIC study did not meet its primary end points of improved OS with durvalumab vs chemotherapy or improved OS or PFS with durvalumab plus tremelimumab vs chemotherapy in patients with ≥25% of tumor cells expressing PD-L1. Exploratory analyses identified a bTMB threshold of ≥20 mutations per megabase for optimal OS benefit with durvalumab plus tremelimumab.

Trial Registration

ClinicalT rials.gov Identifier: NCT02453282

Immunotherapy in gastroesophageal cancers: Current state and future directions

While gastroesophageal (GE) cancers are one of the most common cancers worldwide, unfortunately, the mortality remains high. Commonly used treatment options include surgical resection, chemotherapy, radiotherapy, and molecular targeted therapy, which improve survival only minimally; thus, affirming the dire need for exploring alternative strategies to improve patient outcomes. Immunotherapy, which has revolutionized the world of oncology, has somewhat lagged behind in GE malignancies. Tumor-associated microenvironment and regulatory T cells, alongside cell cycle checkpoints, have been proposed by various studies as the mediators of carcinogenesis in GE cancers. Thus, inhibition of each of these could serve as a possible target of treatment. While the approval of pembrolizumab has provided some hope, it is not enough to override the dismal prognosis that this disease confers. Herein, we discuss the prospects of immunotherapy in this variety of cancer.

Combination Strategies of Checkpoint Immunotherapy in Metastatic Breast Cancer

Checkpoint immunotherapy is emerging as a new therapeutic approach for metastatic breast cancer. Monotherapy of immunoagents against PD1/PD-L1 or CTLA-4 has shown little efficacy in these patients. Recently, to determine the optimal use of immunotherapy, there has been a rapid expansion in the number of clinical trials developing immunotherapy combinations. These combination therapeutic approaches can enhance various aspects of cancer immunity, such as tumor antigenicity or intratumor T cell infiltration, which provides a theoretical basis for combining them with checkpoint immunotherapy to achieve synergistic effects. Here, we review the available data and ongoing efforts to establish the safety and efficacy of immunoagents in combination with chemotherapy, radiotherapy, HER2-targeted therapy, CDK4/6 inhibitors, PARP inhibitors, and another checkpoint immunoagents.

Design and Rationale for a Phase III, Randomized, Placebo-controlled Trial of Durvalumab With or Without Tremelimumab After Concurrent Chemoradiotherapy for Patients With Limited-stage Small-cell Lung Cancer: The ADRIATIC Study

Limited-stage (LS) small-cell lung cancer (SCLC) remains an area of high unmet medical need. The standard-of-care therapy comprises curative-intent platinum-based chemotherapy with concurrent radiotherapy (cCRT), which can be followed by prophylactic brain irradiation and then observation. However, most patients will relapse. Durvalumab (antiprogrammed cell death ligand-1) has enhanced the efficacy outcomes after cCRT for patients with unresectable, stage III non-small-cell lung cancer. Recently, durvalumab combined with platinum-etoposide demonstrated a significant survival benefit compared with platinum-etoposide as first-line treatment of patients with extensive-stage SCLC and has also shown antitumor activity as monotherapy and combined with tremelimumab (anticytotoxic T-lymphocyte-associated antigen-4) in pretreated patients with extensive-stage SCLC. ADRIATIC, a phase III, randomized, double-blind, placebo-controlled, multicenter, global study (ClinicalTrials.gov identifier, NCT03703297), is designed to investigate the efficacy of durvalumab, with or without tremelimumab, as consolidation therapy for patients with LS-SCLC without disease progression after cCRT. Approximately 600 patients with documented histologic or cytologic LS-SCLC, World Health Organization/Eastern Cooperative Oncology Group performance status 0 or 1, and no progression after 4 cycles of cCRT will be randomized (1:1:1) to treatment (durvalumab 1500 mg plus placebo every 4 weeks [q4w] for 4 cycles, followed by durvalumab 1500 mg q4w; durvalumab 1500 mg plus tremelimumab 75 mg q4w for 4 cycles, followed by durvalumab 1500 mg q4w; or dual placebo q4w for 4 cycles, followed by single placebo q4w) within 1 to 42 days of completing cCRT, stratified by stage and receipt of prophylactic brain irradiation. The primary endpoints are progression-free survival and overall survival. The secondary endpoints are overall survival and progression-free survival rates, objective response rate, and safety and tolerability. Recruitment began in September 2018.

Exposure-Response Analysis of Overall Survival for Tremelimumab in Unresectable Malignant Mesothelioma: The Confounding Effect of Disease Status

Tremelimumab, an anti-cytotoxic T-lymphocyte antigen-4 monoclonal antibody that enhances T-cell activation, was evaluated in a randomized, double-blind, placebo-controlled, phase IIb study (NCT01843374) in patients with unresectable malignant mesothelioma. The study demonstrated no clinically meaningful differences in overall survival (OS). The objective of this analysis was to evaluate the relationship of exposure with OS. A population pharmacokinetic (PK) model adequately described the PK data. Three factors (sex, C-reactive protein, and baseline tumor size) were identified as statistically significant PK predictors (P < 0.05 on clearance). A positive association between exposure and OS was observed. However, an association between key baseline factors with OS (regardless of treatment) and imbalances in prognostic factors favoring patients with higher exposure (upper vs. lower PK quartile) was seen. Taken together, these results suggest that the exposure OS relationship observed for tremelimumab in mesothelioma is likely spurious rather than a true association of exposure with efficacy.

E3611-A Randomized Phase II Study of Ipilimumab at 3 or 10 mg/kg Alone or in Combination with High-Dose Interferon-α2b in Advanced Melanoma

PURPOSE

Interferon-α favors a Th1 shift in immunity, and combining with ipilimumab (ipi) at 3 or 10 mg/kg may downregulate CTLA4-mediated suppressive effects, leading to more durable antitumor immune responses. A study of tremelimumab and high-dose interferon-α (HDI) showed promising efficacy, supporting this hypothesis.

PATIENTS AND METHODS

E3611 followed a 2-by-2 factorial design (A: ipi10+HDI; B: ipi10; C: ipi3+HDI; D: ipi3) to evaluate (i) no HDI versus HDI (across ipilimumab doses) and (ii) ipi3 versus ipi10 (across HDI status). We hypothesized that median progression-free survival (PFS) would improve from 3 to 6 months with HDI versus no HDI and with ipi10 versus ipi3.

RESULTS

For eligible and treated patients (N = 81) at a median follow-up time of 29.8 months, median PFS was 4.4 months [95% confidence interval (CI), 2.7-8.2] when ipilimumab was used alone and 7.5 months (95% CI, 5.1-11.0) when HDI was added. Median PFS was 3.8 months (95% CI, 2.6-7.5) with 3 mg/kg ipilimumab and 6.5 months (95% CI, 5.1-13.5) with 10 mg/kg. By study arm, median PFS was 8.0 months (95% CI, 2.8-20.2) in arm A, 6.2 months (95% CI, 2.7-25.7) in B, 5.7 months (95% CI, 1.5-11.1) in C, and 2.8 months (95% CI, 2.6-5.7) in D. The differences in PFS and overall survival (OS) did not reach statistical significance. Adverse events were consistent with the known profiles of ipilimumab and HDI and significantly higher with HDI and ipi10.

CONCLUSIONS

Although PFS was increased, the differences resulting from adding interferon-α or a higher dose of ipilimumab did not reach statistical significance and do not outweigh the added toxicity risks.

Cancer immunotherapy in patients with brain metastases

The exclusion of "real-world" patients from registration clinical trials of cancer immunotherapy represents a significant emerging issue. For instance, a large fraction of cancer patients develops brain metastases during the course of the disease, but results from large prospective clinical trials investigating this considerable proportion of the cancer patient population are currently lacking. To provide a useful tool for the clinician in a "real-world" setting, we have reviewed the available literature regarding the safety and efficacy of immune check-point inhibitors in patients with cancer metastatic to the brain. Overall, these data provide encouraging evidence that these therapeutic agents can induce intracranial objective responses, particularly in patients with asymptomatic and previously untreated brain metastases. Larger prospective studies are needed to confirm these initial results.

Medical management of brain metastases and leptomeningeal disease in patients with breast carcinoma

Breast cancer is the most common malignancy among women and accounts for the second highest number of cancer-related deaths. With patients surviving longer due to advances in systemic control, the incidence of CNS involvement is increasing; however, the management of CNS metastases has not undergone parallel advancements. The blood–brain barrier limits the efficacy of most systemic chemotherapies, and the utilization of surgery and radiation beyond first-line therapy is limited. We will explore the recent developments in the medical management of breast cancer brain metastasis. Beyond traditional chemotherapy, we will also discuss targeted therapies and immunotherapies which may provide a survival benefit to this population and thus, offer further treatment options and a path for future research and treatment advances.

Trial watch: Immune checkpoint blockers for cancer therapy

Immune checkpoint blockers (ICBs) are literally revolutionizing the clinical management of an ever more diversified panel of oncological indications. Although considerable attention persists around the inhibition of cytotoxic T lymphocyte-associated protein 4 (CTLA4) and programmed cell death 1 (PDCD1, best known as PD-1) signaling, several other co-inhibitory T-cell receptors are being evaluated as potential targets for the development of novel ICBs. Moreover, substantial efforts are being devoted to the identification of biomarkers that reliably predict the likelihood of each patient to obtain clinical benefits from ICBs in the absence of severe toxicity. Tailoring the delivery of specific ICBs or combinations thereof to selected patient populations in the context of precision medicine programs constitutes indeed a major objective of the future of ICB-based immunotherapy. Here, we discuss recent preclinical and clinical advances on the development of ICBs for oncological indications.

Basis for molecular diagnostics and immunotherapy for esophageal cancer

INTRODUCTION

Esophageal cancer (EC) is an extremely aggressive neoplasm, diagnosed in about 17,000 Americans every year with a mortality rate of more than 80% within five years and a median overall survival of just 13 months. For decades, the go-to regimen for esophageal cancer patients has been the use of taxane and platinum-based chemotherapy regimens, which has yielded the field's most dire survival statistics. Areas covered: Combination immunotherapy and a more robust molecular diagnostic platform for esophageal tumors could improve patient management strategies and potentially extend lives beyond the current survival figures. Analyzing a panel of biomarkers including those affiliated with taxane and platinum resistance (ERCC1 and TUBB3) as well as immunotherapy effectiveness (PD-L1) would provide oncologists more information on how to optimize first-line therapy for EC. Expert commentary: Of the 12 FDA-approved therapies in EC, zero target the genome. A majority of the approved drugs either target or are effected by proteomic expression. Therefore, a broader understanding of diagnostic biomarkers could give more clarity and direction in treating esophageal cancer in concert with a greater use of immunotherapy.

Phase I study of tremelimumab (CP-675 206) plus PF-3512676 (CPG 7909) in patients with melanoma or advanced solid tumours

Background:

Tremelimumab, a fully human cytotoxic T-lymphocyte antigen 4 monoclonal antibody, and PF-3512676, a Toll-like receptor-9 agonist, are targeted immune modulators that elicit durable single-agent antitumour activity in advanced cancer.

Methods:

To determine the maximum tolerated dose (MTD) of these agents combined during this phase I study, patients received intravenous tremelimumab (6.0, 10.0, or 15.0 mg kg⁻¹) every 12 weeks plus subcutaneous PF-3512676 (0.05, 0.10, or 0.15 mg kg⁻¹) weekly. Primary end points were safety and tolerability; secondary end points included pharmacokinetics and antitumour activity.

Results:

Twenty-one patients with stage IV melanoma (n=17) or advanced solid tumours (n=4) were enrolled. Injection-site reactions (n=21; 100%), influenza-like illness (n=18; 86%), and diarrhoea (n=13; 62%) were the most common treatment-related adverse events (TAEs). Grade ⩾3 TAEs were reported (n=7; 33%). Dose-limiting toxicities (prespecified 6-week observation) occurred in one of the six patients in the 10 mg kg⁻¹ tremelimumab plus 0.05 mg kg⁻¹ PF-3512676 cohort (grade 3 hypothalamopituitary disorder) and two of the six patients in the 15 mg kg⁻¹ tremelimumab plus 0.05 mg kg⁻¹ PF-3512676 cohort (grade 3 diarrhoea). Consequently, 15 mg kg⁻¹ tremelimumab plus 0.05 mg kg⁻¹ PF-3512676 exceeded the MTD. Two melanoma patients achieved durable (⩾170 days) partial response. No human antihuman antibody responses to tremelimumab were observed.

Conclusion:

Weekly PF-3512676 (⩽0.15 mg kg⁻¹) plus tremelimumab (⩽10 mg kg⁻¹ every 12 weeks) was tolerable.

Association of CTLA-4 polymorphisms with improved overall survival in melanoma patients treated with CTLA-4 blockade: a pilot study

CTLA-4 blockade with monoclonal antibodies can lead to cancer regression in patients with metastatic melanoma (MM). CTLA-4 gene polymorphisms may influence the response to anti-CTLA-4 antibodies although few data are available regarding this issue. We analyzed six CTLA-4 single nucleotide polymorphisms (-1661A > G, -1577G > A, -658C > T, -319C > T, +49A > G, and CT60G > A) in 14 Italian MM patients and 45 healthy subjects. We found a significant association between the -1577G/A and CT60G/A genotypes and improved overall survival (Pc < 0.006, Bonferroni corrected), further confirmed by the diplotype analysis (-1577 & CT60 GG-AA diplotype, p < 0.001). A positive trend toward an association between these genotypes and response to therapy was also observed.

Preclinical and clinical activity of the topoisomerase I inhibitor, karenitecin, in melanoma

INTRODUCTION

This review covers the preclinical and clinical activity of the novel camptothecin analog, karenitecin, in melanoma.

AREAS COVERED

While the camptothecins are widely used antitumor agents that inhibit topoisomerase I, their utility is limited by instability, high interpatient variability and the development of drug resistance. Karenitecin was rationally designed to overcome these limitations. The authors review the data on karenitecin in preclinical models and in clinical trials in melanoma using studies published in Medline and reports presented at AACR and ASCO.

EXPERT OPINION

Karenitecin shows activity in melanoma, both as a single agent and in combination. In adverse prognostic factor melanoma, karenitecin showed prolonged disease stabilization in 34% of patients. Because preclinical studies suggested a synergistic interaction between karenitecin and HDAC inhibitors, a schedule-specific combination Phase I-II trial of valproic acid and karenitecin was carried out in heavily pretreated melanoma patients which showed a benefit rate in 47% patients with acceptable toxicity. The treatment for melanoma is in rapid transition and genomic profiling is now an integral part, and hence the optimal use of karenitecin in melanoma should be re-evaluated with regard to specific mutational status.

Safety and efficacy of combination immunotherapy with interferon alfa-2b and tremelimumab in patients with stage IV melanoma

PURPOSE

We tested the hypothesis that the combination of tremelimumab and interferon alfa-2b acting via different and possibly synergistic mechanisms would overcome tumor immune tolerance and lead to significant and durable clinical responses.

PATIENTS AND METHODS

We conducted a phase II study in which patients were administered tremelimumab 15 mg/kg/course (three cycles [one cycle = 4 weeks]) intravenously every 12 weeks. High-dose interferon alfa-2b (HDI) was administered concurrently, including intravenous induction at 20 MU/m2/d for 5 d/wk for 4 weeks followed by maintenance at 10 MU/m2/d subcutaneously three times a week for 8 weeks per course. From course 2 onward, HDI maintenance was administered subcutaneously.

RESULTS

Thirty-seven patients with American Joint Committee on Cancer stage IV (9M1a, 6M1b, and 22M1c) were enrolled. Two patients had previously treated brain metastases. Grades 3 and 4 toxicities included neutropenia (six patients; 17%), diarrhea/colitis (four patients; 11%), liver enzyme increase (four patients; 11%), rash (four patients; 11%), fatigue (15 patients; 40%), and anxiety/depression (five patients; 14%). Response data were available for 35 patients. The best objective response rate (RR; Response Evaluation Criteria in Solid Tumors) by intention to treat was 24% (90% CI, 13% to 36%; four complete responses [CRs] and five partial responses [PRs] that lasted 6, 6, > 12, > 14, > 18, 20, > 28, 30, and > 37 months, respectively). Fourteen patients (38%) had stable disease (SD) that lasted 1.5 to 21 months. The median progression-free survival was 6.4 months (95% CI, 3.3 to 12.1 months). The median overall survival (OS) was 21 months (95% CI, 9.5 to not reached). There was a weak association between therapy-induced autoimmunity and clinical benefits (CR/PR/SD; P = .0059), baseline C-reactive protein (CRP) less than or equal to 2.7× the upper limit of normal and clinical benefits (P = .0494) and improved probability of survival (P = .0032), and baseline lymphocyte count of at least 1,000/μL and response (CR/PR; P = .0183) and clinical benefits (CR/PR/SD; P = .0255). Biomarker associations were not significant after adjustment for multiple comparisons.

CONCLUSION

HDI can be administered combined with tremelimumab with acceptable toxicity and promising durable antitumor efficacy that warrant further testing in a randomized trial.

Current experience with CTLA4-blocking monoclonal antibodies for the treatment of solid tumors

Monoclonal antibodies (mAbs) specific for cytotoxic T lymphocyte-associated antigen 4 (CTLA4) are a novel form of immunotherapy for treatment of patients with advanced cancers. These anti-CTLA4 mAbs prevent normal downregulation of the immune system, thus prolonging and enhancing T-cell activation and potentially promoting an antitumor immune response. Clinical studies in patients with advanced cancers have indicated that CTLA4 blockade with mAbs is associated with antitumor activity in a small percentage of patients and has a manageable toxicity profile. The key limitations for broader applicability of this mode of therapy are better definition of the mechanism that leads to tumor rejection and the validation of favorable observations in single-arm studies into prospectively randomized clinical trials.

Tremelimumab in combination with exemestane in patients with advanced breast cancer and treatment-associated modulation of inducible costimulator expression on patient T cells

PURPOSE

Tremelimumab is a fully human monoclonal antibody specific for CTL-associated antigen 4 (CTLA4) with single-agent activity in certain tumors but has not been evaluated in patients with breast cancer.

EXPERIMENTAL DESIGN

In a phase 1 study, 26 patients with advanced, hormone-responsive breast cancer received tremelimumab (3-10 mg/kg) every 28 days or every 90 days plus exemestane 25 mg daily. The objectives were to determine safety and the maximum tolerated dose (MTD) of tremelimumab with exemestane and, secondarily, to assess tumor response, pharmacokinetics, and immune pharmacodynamics.

RESULTS

Most treatment-related adverse events were mild to moderate with the most common being diarrhea (46% of patients), pruritus (42%), constipation (23%), and fatigue (23%). Dose-limiting toxicities were transient serum transaminase elevations (one patient) and diarrhea (four patients). The MTD of tremelimumab with exemestane was 6 mg/kg every 90 days. Among 13 patients treated at the MTD, none developed grade 3 or 4 treatment-related diarrhea. No pharmacokinetic interaction was observed between tremelimumab and exemestane. The best overall response was stable disease for >or=12 weeks in 11 patients (42%). Treatment was associated in most patients with increased peripheral CD4+ and CD8+ T cells expressing inducible costimulator (ICOS) and a marked increase in the ratio of ICOS+ T cells to FoxP3+ regulatory T cells.

CONCLUSIONS

Tremelimumab plus exemestane is tolerable in patients with hormone-responsive advanced breast cancer. Treatment is associated with increased ICOS+ T cells, which likely signals immune activation secondary to CTL-associated antigen 4 blockade.

Novel therapeutics for the treatment of metastatic melanoma

Metastatic malignant melanoma is an incurable disease with a median survival of 8.5 months and a probability of surviving 5 years after the diagnosis of less than 5%. To date, no systemic therapy has meaningfully changed these survival end points. Currently, in the USA the FDA has approved three agents for the treatment of metastatic melanoma: hydroxyurea, dacarbazine and interleukin-2. None of these have demonstrated a meaningfully prolonged survival of patients with metastatic melanoma. Therefore, a number of innovative therapeutic strategies have been pursued to improve outcomes, including immune therapy, tyrosine kinase inhibitors and angiogenesis inhibitors. Herein, we review some of the recent advances in novel therapeutic developments for the treatment of metastatic melanoma.