Overall Survival with Durvalumab after Chemoradiotherapy in Stage III NSCLC.

BACKGROUND: An earlier analysis in this phase 3 trial showed that durvalumab significantly prolonged progression-free survival, as compared with placebo, among patients with stage III, unresectable non-small-cell lung cancer (NSCLC) who did not have disease progression after concurrent chemoradiotherapy. Here we report the results for the second primary end point of overall survival. METHODS: We randomly assigned patients, in a 2:1 ratio, to receive durvalumab intravenously, at a dose of 10 mg per kilogram of body weight, or matching placebo every 2 weeks for up to 12 months. Randomization occurred 1 to 42 days after the patients had received chemoradiotherapy and was stratified according to age, sex, and smoking history. The primary end points were progression-free survival (as assessed by blinded independent central review) and overall survival. Secondary end points included the time to death or distant metastasis, the time to second progression, and safety. RESULTS: Of the 713 patients who underwent randomization, 709 received the assigned intervention (473 patients received durvalumab and 236 received placebo). As of March 22, 2018, the median follow-up was 25.2 months. The 24-month overall survival rate was 66.3% (95% confidence interval [CI], 61.7 to 70.4) in the durvalumab group, as compared with 55.6% (95% CI, 48.9 to 61.8) in the placebo group (two-sided P=0.005). Durvalumab significantly prolonged overall survival, as compared with placebo (stratified hazard ratio for death, 0.68; 99.73% CI, 0.47 to 0.997; P=0.0025). Updated analyses regarding progression-free survival were similar to those previously reported, with a median duration of 17.2 months in the durvalumab group and 5.6 months in the placebo group (stratified hazard ratio for disease progression or death, 0.51; 95% CI, 0.41 to 0.63). The median time to death or distant metastasis was 28.3 months in the durvalumab group and 16.2 months in the placebo group (stratified hazard ratio, 0.53; 95% CI, 0.41 to 0.68). A total of 30.5% of the patients in the durvalumab group and 26.1% of those in the placebo group had grade 3 or 4 adverse events of any cause; 15.4% and 9.8% of the patients, respectively, discontinued the trial regimen because of adverse events. CONCLUSIONS: Durvalumab therapy resulted in significantly longer overall survival than placebo. No new safety signals were identified. (Funded by AstraZeneca; PACIFIC ClinicalTrials.gov number, NCT02125461 .).

Patient-reported outcomes with durvalumab by PD-L1 expression and prior chemoradiotherapy-related variables in unresectable stage III non-small-cell lung cancer.

Aim: We retrospectively investigated the impact of tumor PD-L1 expression and prior chemoradiotherapy (CRT)-related variables on patient-reported outcomes (PROs) from PACIFIC. Patients & methods: PACIFIC was a Phase III study of durvalumab versus placebo after CRT in patients with unresectable, stage III non-small-cell lung cancer. If available, pre-CRT tumor tissue was tested for PD-L1 tumor-cell expression, scored at prespecified (25%) and post-hoc (1%) cut-offs. PROs were assessed using EORTC QLQ C30/-LC13. Results: Similar to the intent-to-treat (ITT) population, most PROs remained stable over time across PD-L1 and CRT subgroups, with few clinically relevant differences between treatment arms. Time to deterioration was generally similar to the ITT population. Conclusion: Neither PD-L1 expression nor prior CRT-related variables influenced PROs with durvalumab therapy. Clinical trial registration: NCT02125461 (ClinicalTrials.gov).

Assessing the Influence of Subsequent Immunotherapy on Overall Survival in Patients with Unresectable Stage III Non-Small Cell Lung Cancer from the PACIFIC Study.

BACKGROUND: Historically, the standard of care for patients with unresectable, Stage III non-small cell lung cancer had been concurrent chemoradiotherapy. However, outcomes had been poor, with approximately 15% to 32% of patients alive at 5 years. In the placebo-controlled Phase III A PACIFIC trial, consolidation treatment with durvalumab after concurrent chemoradiotherapy significantly improved overall survival (OS) and progression-free survival in patients with unresectable, Stage III non-small cell lung cancer, establishing this regimen as a new standard of care in this setting. In the PACIFIC trial, crossover between treatment arms (durvalumab or placebo) was not permitted. However, after discontinuation from study treatment, patients from both arms of PACIFIC could switch to subsequent anticancer therapy, including durvalumab and other immunotherapies, which is known to influence standard intention-to-treat analysis of OS, potentially underestimating the effect of an experimental drug. Moreover, the introduction of immunotherapies has demonstrated marked improvements in the postprogression, metastatic non-small cell lung cancer setting. OBJECTIVE: To examine the influence of subsequent immunotherapy on OS in the PACIFIC trial. METHODS: Both a Rank Preserving Structural Failure Time Model (RPSFTM) and modified 2-stage method were used. RPSFTM assumes that a patient's survival time with no immunotherapy (counterfactual survival time) is equal to the observed time influenced by immunotherapy, multiplied by an acceleration factor, plus the time not influenced. The modified 2-stage method estimates the effect of immunotherapy by comparing postsubsequent-treatment-initiation survival times between patients with and without subsequent immunotherapy. In both models, OS was adjusted to reflect a hypothetical scenario in which no patients received subsequent immunotherapy. RPSFTM was also used for scenarios in which subsequent immunotherapy was received by increasing proportions of placebo patients but none of the durvalumab patients. RESULTS: In the intention-to-treat analysis (3-year follow-up), durvalumab improved OS versus placebo (stratified hazard ratio = 0.69; 95% CI, 0.55-0.86). Overall, 10% and 27% of durvalumab and placebo patients, respectively, received subsequent immunotherapy. With subsequent immunotherapy removed from both arms, estimated hazard ratio was 0.66 (95% CI, 0.53-0.84) with RPSFTM and 0.68 (95% CI, 0.54-0.85) with the modified 2-stage method. With subsequent immunotherapy removed from the durvalumab arm only (RPSFTM), estimated hazard ratio increased as the proportion of placebo patients receiving subsequent immunotherapy increased, up to 0.75 (95% CI, 0.60-0.94) maximum (assuming all placebo patients with subsequent treatment received immunotherapy). CONCLUSIONS: Results were consistent with the intention-to-treat analysis, supporting the conclusion that durvalumab after chemoradiotherapy provides substantial OS benefit in patients with Stage III, unresectable non-small cell lung cancer. ClinicalTrials.gov identifier: NCT02125461 (Curr Ther Res Clin Exp. 2021; 82:XXX-XXX).

Durvalumab after Chemoradiotherapy in Stage III Non-Small-Cell Lung Cancer.

BACKGROUND: Most patients with locally advanced, unresectable, non-small-cell lung cancer (NSCLC) have disease progression despite definitive chemoradiotherapy (chemotherapy plus concurrent radiation therapy). This phase 3 study compared the anti-programmed death ligand 1 antibody durvalumab as consolidation therapy with placebo in patients with stage III NSCLC who did not have disease progression after two or more cycles of platinum-based chemoradiotherapy. METHODS: We randomly assigned patients, in a 2:1 ratio, to receive durvalumab (at a dose of 10 mg per kilogram of body weight intravenously) or placebo every 2 weeks for up to 12 months. The study drug was administered 1 to 42 days after the patients had received chemoradiotherapy. The coprimary end points were progression-free survival (as assessed by means of blinded independent central review) and overall survival (unplanned for the interim analysis). Secondary end points included 12-month and 18-month progression-free survival rates, the objective response rate, the duration of response, the time to death or distant metastasis, and safety. RESULTS: Of 713 patients who underwent randomization, 709 received consolidation therapy (473 received durvalumab and 236 received placebo). The median progression-free survival from randomization was 16.8 months (95% confidence interval [CI], 13.0 to 18.1) with durvalumab versus 5.6 months (95% CI, 4.6 to 7.8) with placebo (stratified hazard ratio for disease progression or death, 0.52; 95% CI, 0.42 to 0.65; P<0.001); the 12-month progression-free survival rate was 55.9% versus 35.3%, and the 18-month progression-free survival rate was 44.2% versus 27.0%. The response rate was higher with durvalumab than with placebo (28.4% vs. 16.0%; P<0.001), and the median duration of response was longer (72.8% vs. 46.8% of the patients had an ongoing response at 18 months). The median time to death or distant metastasis was longer with durvalumab than with placebo (23.2 months vs. 14.6 months; P<0.001). Grade 3 or 4 adverse events occurred in 29.9% of the patients who received durvalumab and 26.1% of those who received placebo; the most common adverse event of grade 3 or 4 was pneumonia (4.4% and 3.8%, respectively). A total of 15.4% of patients in the durvalumab group and 9.8% of those in the placebo group discontinued the study drug because of adverse events. CONCLUSIONS: Progression-free survival was significantly longer with durvalumab than with placebo. The secondary end points also favored durvalumab, and safety was similar between the groups. (Funded by AstraZeneca; PACIFIC ClinicalTrials.gov number, NCT02125461 .).

Patient-reported outcomes with durvalumab after chemoradiotherapy in stage III, unresectable non-small-cell lung cancer (PACIFIC): a randomised, controlled, phase 3 study.

BACKGROUND: In the ongoing, phase 3 PACIFIC trial, durvalumab improved the primary endpoints of progression-free survival and overall survival compared with that for placebo, with similar safety, in patients with unresectable, stage III non-small-cell lung cancer. In this analysis, we aimed to evaluate one of the secondary endpoints, patient-reported outcomes (PROs). METHODS: PACIFIC is an ongoing, international, multicentre, double-blind, randomised, controlled, phase 3 trial. Eligible patients were aged at least 18 years, had a WHO performance status of 0 or 1, with histologically or cytologically documented stage III, unresectable non-small-cell lung cancer, for which they had received at least two cycles of platinum-based chemoradiotherapy, with no disease progression after this treatment. We randomly assigned patients (2:1) using an interactive voice response system and a blocked design (block size=3) stratified by age, sex, and smoking history to receive 10 mg/kg intravenous durvalumab or matching placebo 1-42 days after concurrent chemoradiotherapy, then every 2 weeks up to 12 months. The primary endpoints of progression-free survival and overall survival have been reported previously. PROs were a prespecified secondary outcome. We assessed PRO symptoms, functioning, and global health status or quality of life in the intention-to-treat population with the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire-Core 30 (QLQ-C30) version 3 and its lung cancer module, the Quality of Life Questionnaire-Lung Cancer 13 (QLQ-LC13) at the time of random allocation to groups, at weeks 4 and 8, every 8 weeks until week 48, and then every 12 weeks until progression. Changes from baseline to 12 month in key symptoms were analysed with mixed model for repeated measures (MMRM) and time-to-event analyses. A 10-point or greater change from baseline (deterioration or improvement) was deemed clinically relevant. This study is registered with ClinicalTrials.gov, NCT02125461, and EudraCT, 2014-000336-42. FINDINGS: Between May 9, 2014, and April 22, 2016, 476 patients were assigned to receive durvalumab, and 237 patients were assigned to receive placebo. As of March 22, 2018, the median follow-up was 25·2 months (IQR 14·1-29·5). More than 79% of patients given durvalumab and more than 82% of patients given placebo completed questionnaires up to week 48. Between baseline and 12 months, the prespecified longitudinal PROs of interest, cough (MMRM-adjusted mean change 1·8 [95% CI 0·06 to 3·54] in the durvalumab group vs 0·7 [-1·91 to 3·30] in the placebo group), dyspnoea (3·1 [1·75 to 4·36] vs 1·4 [-0·51 to 3·34]), chest pain (-3·1 [-4·57 to -1·60] vs -3·5 [-5·68 to -1·29]), fatigue (-3·0 [-4·53 to -1·50] vs -5·2 [-7·45 to -2·98]), appetite loss (-5·8 [-7·28 to -4·36] vs -7·0 [-9·17 to -4·87]), physical functioning (0·1 [-1·10 to 1·28] vs 2·0 [0·22 to 3·73]), and global health status or quality of life (2·6 [1·21 to 3·94] vs 1·8 [-0·25 to 3·81]) remained stable with both treatments, with no clinically relevant changes from baseline. The between-group differences in changes from baseline to 12 months in cough (difference in adjusted mean changes 1·1, 95% CI -1·89 to 4·11), dyspnoea (1·6, -0·58 to 3·87), chest pain (0·4, -2·13 to 2·93), fatigue (2·2, -0·38 to 4·78), appetite loss (1·2, -1·27 to 3·67), physical functioning (-1·9, -3·91 to 0·15), or global health status or quality of life (0·8, -1·55 to 3·14) were not clinically relevant. Generally, there were no clinically important between-group differences in time to deterioration of prespecified key PRO endpoints. INTERPRETATION: Our findings suggest that a clinical benefit with durvalumab can be attained without compromising PROs. This result is of note because the previous standard of care was observation alone, with no presumed detriment to PROs. FUNDING: AstraZeneca.

A Pilot Study of Sirolimus in Subjects with Cowden Syndrome or Other Syndromes Characterized by Germline Mutations in PTEN.

LESSONS LEARNED: This is the first human interventional study in patients with Cowden syndrome that is driven by inactivation of germline PTEN gene.Single-agent sirolimus, a mTOR inhibitor, suppressed mTOR signaling in surrogate human tissues without significant toxicity. BACKGROUND: Cowden syndrome is characterized by inactivating germline PTEN mutations, which can lead to activation of the PI3K-Akt-mTOR pathway. METHODS: Adult subjects with germline PTEN mutation who met international diagnostic criteria for Cowden syndrome and who had Eastern Cooperative Oncology Group (ECOG) performance status 0-2 and adequate organ function were enrolled. Subjects were treated with a 56-day course of daily oral sirolimus. In addition to symptom assessment and physical examination, dermatologic, endoscopic, neurologic (cerebellar), and radiographic assessments were conducted. Inhibition of the mTOR pathway in benign skin and gastrointestinal (GI) lesion was assessed by immunohistochemistry. RESULTS: A total of 18 patients and 16 families were enrolled. PTEN mutations were located at exons 1-8. Regression of skin and GI lesions was observed by dermoscopy or endoscopy. Neurological evaluation showed improvement in cerebellar function score at 1 month. Immunohistochemistry (IHC) analysis in skin and GI benign lesions showed a decrease in the ratio of phosphorylated (p)S6 to total S6 in response to sirolimus. Ratios of pS6K to total S6 at days 14 and 56 were significantly lower than at baseline (p = .0026, p = .00391, respectively). A 56-day course of sirolimus was well tolerated. CONCLUSION: A 56-day course of sirolimus was well tolerated in subjects with Cowden syndrome and was associated with some evidence of improvement in symptoms, skin and GI lesions, cerebellar function, and decreased mTOR signaling.

Durvalumab as third-line or later treatment for advanced non-small-cell lung cancer (ATLANTIC): an open-label, single-arm, phase 2 study.

BACKGROUND: Immune checkpoint inhibitors are a new standard of care for patients with advanced non-small-cell lung cancer (NSCLC) without EGFR tyrosine kinase or anaplastic lymphoma kinase (ALK) genetic aberrations (EGFR-/ALK-), but clinical benefit in patients with EGFR mutations or ALK rearrangements (EGFR+/ALK+) has not been shown. We assessed the effect of durvalumab (anti-PD-L1) treatment in three cohorts of patients with NSCLC defined by EGFR/ALK status and tumour expression of PD-L1. METHODS: ATLANTIC is a phase 2, open-label, single-arm trial at 139 study centres in Asia, Europe, and North America. Eligible patients had advanced NSCLC with disease progression following at least two previous systemic regimens, including platinum-based chemotherapy (and tyrosine kinase inhibitor therapy if indicated); were aged 18 years or older; had a WHO performance status score of 0 or 1; and measurable disease per Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. Key exclusion criteria included mixed small-cell lung cancer and NSCLC histology; previous exposure to any anti-PD-1 or anti-PD-L1 antibody; and any previous grade 3 or worse immune-related adverse event while receiving any immunotherapy agent. Patients in cohort 1 had EGFR+/ALK+ NSCLC with at least 25%, or less than 25%, of tumour cells with PD-L1 expression. Patients in cohorts 2 and 3 had EGFR-/ALK- NSCLC; cohort 2 included patients with at least 25%, or less than 25%, of tumour cells with PD-L1 expression, and cohort 3 included patients with at least 90% of tumour cells with PD-L1 expression. Patients received durvalumab (10 mg/kg) every 2 weeks, via intravenous infusion, for up to 12 months. Retreatment was allowed for patients who benefited but then progressed after completing 12 months. The primary endpoint was the proportion of patients with increased tumour expression of PD-L1 (defined as ≥25% of tumour cells in cohorts 1 and 2, and ≥90% of tumour cells in cohort 3) who achieved an objective response, assessed in patients who were evaluable for response per independent central review according to RECIST version 1.1. Safety was assessed in all patients who received at least one dose of durvalumab and for whom any post-dose data were available. The trial is ongoing, but is no longer open to accrual, and is registered with ClinicalTrials.gov, number NCT02087423. FINDINGS: Between Feb 25, 2014, and Dec 28, 2015, 444 patients were enrolled and received durvalumab: 111 in cohort 1, 265 in cohort 2, and 68 in cohort 3. Among patients with at least 25% of tumour cells expressing PD-L1 who were evaluable for objective response per independent central review, an objective response was achieved in 9 (12·2%, 95% CI 5·7-21·8) of 74 patients in cohort 1 and 24 (16·4%, 10·8-23·5) of 146 patients in cohort 2. In cohort 3, 21 (30·9%, 20·2-43·3) of 68 patients achieved an objective response. Grade 3 or 4 treatment-related adverse events occurred in 40 (9%) of 444 patients overall: six (5%) of 111 patients in cohort 1, 22 (8%) of 265 in cohort 2, and 12 (18%) of 68 in cohort 3. The most common treatment-related grade 3 or 4 adverse events were pneumonitis (four patients [1%]), elevated gamma-glutamyltransferase (four [1%]), diarrhoea (three [1%]), infusion-related reaction (three [1%]), elevated aspartate aminotransferase (two [<1%]), elevated transaminases (two [<1%]), vomiting (two [<1%]), and fatigue (two [<1%]). Treatment-related serious adverse events occurred in 27 (6%) of 444 patients overall: five (5%) of 111 patients in cohort 1, 14 (5%) of 265 in cohort 2, and eight (12%) of 68 in cohort 3. The most common serious adverse events overall were pneumonitis (five patients [1%]), fatigue (three [1%]), and infusion-related reaction (three [1%]). Immune-mediated events were manageable with standard treatment guidelines. INTERPRETATION: In patients with advanced and heavily pretreated NSCLC, the clinical activity and safety profile of durvalumab was consistent with that of other anti-PD-1 and anti-PD-L1 agents. Responses were recorded in all cohorts; the proportion of patients with EGFR-/ALK- NSCLC (cohorts 2 and 3) achieving a response was higher than the proportion with EGFR+/ALK+ NSCLC (cohort 1) achieving a response. The clinical activity of durvalumab in patients with EGFR+ NSCLC with ≥25% of tumour cells expressing PD-L1 was encouraging, and further investigation of durvalumab in patients with EGFR+/ALK+ NSCLC is warranted. FUNDING: AstraZeneca.

Nelfinavir inhibits maturation and export of herpes simplex virus 1.

UNLABELLED: Nelfinavir (NFV) is an HIV-1 protease inhibitor with demonstrated antiviral activity against herpes simplex virus 1 (HSV-1) and several other herpesviruses. However, the stages of HSV-1 replication inhibited by NFV have not been explored. In this study, we investigated the effects of NFV on capsid assembly and envelopment. We confirmed the inhibitory effects of NFV on HSV-1 replication by plaque assay and found that treatment with NFV did not affect capsid assembly, activity of the HSV-1 maturational protease, or formation of DNA-containing capsids in the nucleus. Confocal and electron microscopy studies showed that these capsids were transported to the cytoplasm but failed to complete secondary envelopment and subsequent exit from the cell. Consistent with the microscopy results, a light-scattering band corresponding to enveloped virions was not evident following sucrose gradient rate-velocity separation of lysates from drug-treated cells. Evidence of a possibly related effect of NFV on viral glycoprotein maturation was also discovered. NFV also inhibited the replication of an HSV-1 thymidine kinase mutant resistant to nucleoside analogues such as acyclovir. Given that NFV is neither a nucleoside mimic nor a known inhibitor of nucleic acid synthesis, this was expected and suggests its potential as a coinhibitor or alternate antiviral therapeutic agent in cases of resistance. IMPORTANCE: Nelfinavir (NFV) is a clinically important antiviral drug that inhibits production of infectious HIV. It was reported to inhibit herpesviruses in cell culture. Herpes simplex virus 1 (HSV-1) infections are common and often associated with several diseases. The studies we describe here confirm and extend earlier findings by investigating how NFV interferes with HSV-1 replication. We show that early steps in virus formation (e.g., assembly of DNA-containing capsids in the nucleus and their movement into the cytoplasm) appear to be unaffected by NFV, whereas later steps (e.g., final envelopment in the cytoplasm and release of infectious virus from the cell) are severely restricted by the drug. Our findings provide the first insight into how NFV inhibits HSV-1 replication and suggest that this drug may have applications for studying the herpesvirus envelopment process. Additionally, NFV may have therapeutic value alone or in combination with other antivirals in treating herpesvirus infections.

Inhibition of the NOTCH and mTOR pathways by nelfinavir as a novel treatment for T cell acute lymphoblastic leukemia.

T cell acute lymphoblastic leukemia (T­ALL), a neoplasm derived from T cell lineage­committed lymphoblasts, is characterized by genetic alterations that result in activation of oncogenic transcription factors and the NOTCH1 pathway activation. The NOTCH is a transmembrane receptor protein activated by γ­secretase. γ­secretase inhibitors (GSIs) are a NOTCH­targeted therapy for T­ALL. However, their clinical application has not been successful due to adverse events (primarily gastrointestinal toxicity), limited efficacy, and drug resistance caused by several mechanisms, including activation of the AKT/mTOR pathway. Nelfinavir is an human immunodeficiency virus 1 aspartic protease inhibitor and has been repurposed as an anticancer drug. It acts by inducing endoplasmic reticulum (ER) stress and inhibiting the AKT/mTOR pathway. Thus, it was hypothesized that nelfinavir might inhibit the NOTCH pathway via γ­secretase inhibition and blockade of aspartic protease presenilin, which would make nelfinavir effective against NOTCH­associated T­ALL. The present study assessed the efficacy of nelfinavir against T­ALL cells and investigated mechanisms of action in vitro and in preclinical treatment studies using a SCL­LMO1 transgenic mouse model. Nelfinavir blocks presenilin 1 processing and inhibits γ­secretase activity as well as the NOTCH1 pathway, thus suppressing T­ALL cell viability. Additionally, microarray analysis of nelfinavir­treated T­ALL cells showed that nelfinavir upregulated mRNA levels of CHAC1 (glutathione­specific γ­glutamylcyclotransferase 1, a negative regulator of NOTCH) and sestrin 2 (SESN2; a negative regulator of mTOR). As both factors are upregulated by ER stress, this confirmed that nelfinavir induced ER stress in T­ALL cells. Moreover, nelfinavir suppressed NOTCH1 mRNA expression in microarray analyses. These findings suggest that nelfinavir inhibited the NOTCH1 pathway by downregulating NOTCH1 mRNA expression, upregulating CHAC1 and suppressing γ­secretase via presenilin 1 inhibition and the mTOR pathway by upregulating SESN2 via ER stress induction. Further, nelfinavir exhibited therapeutic efficacy against T­ALL in an SCL­LMO1 transgenic mouse model. Collectively, these findings highlight the potential of nelfinavir as a novel therapeutic candidate for treatment of patients with T­ALL.

A Cyp2a polymorphism predicts susceptibility to NNK-induced lung tumorigenesis in mice.

Lung tumors from smokers as well as lung tumors from mice exposed to tobacco carcinogens such as 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), often carry mutations in K-ras, which activates downstream-signaling pathways such as PI3K/AKT/mTOR pathway. Mice with genetic deletion of one of three isoforms of AKT were used to investigate the role of AKT in mutant K-ras-induced lung tumorigenesis in mice. Although deletion of Akt1 or Akt2 decreased NNK-induced lung tumor formation by 90%, deletion of Akt2 failed to decrease lung tumorigenesis in two other mouse models driven by mutant K-ras. Genetic mapping showed that Akt2 was tightly linked to the cytochrome P450 Cyp2a locus on chromosome 7. Consequently, targeted deletion of Akt2 created linkage to a strain-specific Cyp2a5 polymorphism that decreased activation of NNK in vitro. Mice with this Cyp2a5 polymorphism had decreased NNK-induced DNA adduct formation in vivo and decreased NNK-induced lung tumorigenesis. These studies support human epidemiological studies linking CYP2A polymorphisms with lung cancer risk in humans and highlight the need to confirm phenotypes of genetically engineered mice in multiple mouse strains.

Combining Nelfinavir With Chloroquine Inhibits In Vivo Growth of Human Lung Cancer Xenograft Tumors.

BACKGROUND/AIM: Nelfinavir is a human immunodeficiency virus protease inhibitor that is currently being repositioned as an anticancer drug. Chloroquine, an anti-malarial lysosomotropic drug, inhibits autophagy. It has been reported that the combination of nelfinavir and chloroquine significantly enhances endoplasmic reticulum (ER) stress and induces selective cell death in multiple cell line models (in vitro). MATERIALS AND METHODS: We assessed the effects of the combination of these drugs on human NSCLC cell lines in vitro using cell proliferation assay and performed preclinical treatment studies using cell line-derived xenograft mouse models in vivo. RESULTS: In vitro, this combination enhanced inhibition of NSCLC cell proliferation with increased proteotoxicity, including ER stress, and apoptosis. In vivo, the growth of human NSCLC xenograft tumors was inhibited, which correlated with increased apoptosis and induction of ER stress as well as NSCLC growth in vitro. CONCLUSION: Our findings suggest that the induction of proteotoxicity provides a promising new target for developing anticancer drugs.

Nelfinavir Inhibits the Growth of Small-cell Lung Cancer Cells and Patient-derived Xenograft Tumors.

BACKGROUND/AIM: Small-cell lung cancer (SCLC) is aggressive and confers poor prognosis. Although SCLC shows more response to chemotherapy than other types of lung cancer, it is difficult to cure because of its frequent recurrence. New drugs and molecular targets need to be identified. MATERIALS AND METHODS: We investigated the effect of nelfinavir, an HIV protease inhibitor, on SCLC cells and in preclinical treatment studies using SCLC patient-derived xenograft (PDX) mouse models. RESULTS: Nelfinavir inhibited SCLC cell proliferation and induced cell death in vitro, which was caused by induction of the unfolded protein response (UPR), inhibition of mammalian/mechanistic target of rapamycin (mTOR) activation, and reduction in the expression of SCLC-related molecules such as achaete-scute homolog 1 (ASCL1). In vivo, nelfinavir inhibited the growth of SCLC PDX tumors, which correlated with the induction of UPR and reduced expression of ASCL1. CONCLUSION: Nelfinavir is highly effective in SCLC in vitro and in vivo, suggesting possible incorporation of nelfinavir into clinical trials for patients with SCLC.

Durvalumab After Concurrent Chemoradiotherapy in Elderly Patients With Unresectable Stage III Non-Small-Cell Lung Cancer (PACIFIC).

BACKGROUND: The PACIFIC trial demonstrated that consolidation durvalumab significantly improved PFS and OS (the primary endpoints) vs. placebo in patients with unresectable, stage III NSCLC whose disease had not progressed after platinum-based, concurrent chemoradiotherapy (CRT). We report exploratory analyses of outcomes from PACIFIC by age. PATIENTS AND METHODS: Patients were randomized 2:1 (1-42 days post-CRT) to receive 12-months' durvalumab (10 mg/kg intravenously every-2-weeks) or placebo. We analyzed PFS and OS (unstratified Cox-proportional-hazards models), safety and patient-reported outcomes (PROs: symptoms, functioning, and global-health-status/quality-of-life) in subgroups defined by a post-hoc 70-year age threshold. Data cut-off for PFS was February 13, 2017 and for OS, safety and PROs was March 22, 2018. RESULTS: Overall, 158 of 713 (22.2%) and 555 of 713 (77.8%) randomized patients were aged ≥70 and <70 years, respectively. Durvalumab improved PFS and OS among patients aged ≥70 (PFS: hazard ratio [HR], 0.62 [95% CI, 0.41-0.95]; OS: HR, 0.78 [95% CI, 0.50-1.22]) and <70 (PFS: HR, 0.53 [95% CI, 0.42-0.67]; OS: HR, 0.66 [95% CI, 0.51-0.87]), although the estimated HR-95% CI for OS crossed one among patients aged ≥70. Durvalumab exhibited a manageable safety profile and did not detrimentally affect PROs vs. placebo, regardless of age; grade 3/4 (41.6% vs. 25.5%) and serious adverse events (42.6% vs. 25.5%) were more common with durvalumab vs. placebo among patients aged ≥70. CONCLUSION: Durvalumab was associated with treatment benefit, manageable safety, and no detrimental impact on PROs, irrespective of age, suggesting that elderly patients with unresectable, stage III NSCLC benefit from treatment with consolidation durvalumab after CRT. However, small subgroup sizes and imbalances in baseline factors prevent robust conclusions.

Impact of prior chemoradiotherapy-related variables on outcomes with durvalumab in unresectable Stage III NSCLC (PACIFIC).

INTRODUCTION: The PACIFIC trial demonstrated that durvalumab significantly improved progression-free and overall survival (PFS/OS), versus placebo, in patients with Stage III NSCLC and stable or responding disease following concurrent, platinum-based chemoradiotherapy (CRT). A range of CT and RT regimens were permitted, and used, in the trial. We report post-hoc, exploratory analyses of clinical outcomes from PACIFIC according to CRT-related variables. METHODS: Patients were randomized 2:1 (1-42 days post-CRT) to up to 12 months durvalumab (10 mg/kg intravenously every 2 weeks) or placebo. Efficacy and safety were analyzed in patient subgroups defined by the following baseline variables: platinum-based CT (cisplatin/carboplatin); vinorelbine, etoposide, or taxane-based CT (all yes/no); total RT dose (<60 Gy/60-66 Gy/>66 Gy); time from last RT dose to randomization (<14 days/≥14 days); and use of pre-CRT induction CT (yes/no). Treatment effects for time-to-event endpoints were estimated by hazard ratios (HRs) from unstratified Cox-proportional-hazards models. RESULTS: Overall, 713 patients were randomized, of whom 709 received treatment in either the durvalumab (n/N = 473/476) or placebo arms (n/N = 236/237). Durvalumab improved PFS, versus placebo, across all subgroups (median follow up, 14.5 months; HR range, 0.34-0.63). Durvalumab improved OS across most subgroups (median follow up, 25.2 months; HR range, 0.35-0.86); however, the 95 % confidence interval (CI) of the estimated treatment effect crossed one for the subgroups of patients who received induction CT (HR, 0.78 [95 % CI, 0.51-1.20]); carboplatin (0.86 [0.60-1.23]); vinorelbine (0.79 [0.49-1.27]); and taxane-based CT (0.73 [0.51-1.04]); and patients who were randomized ≥14 days post-RT (0.81 [0.62-1.06]). Safety was broadly similar across the CRT subgroups. CONCLUSION: Durvalumab prolonged PFS and OS irrespective of treatment variables related to prior CRT to which patients with Stage III NSCLC had previously stabilized or responded. Limited patient numbers and imbalances in baseline factors in each subgroup preclude robust conclusions.

Resistance to Durvalumab and Durvalumab plus Tremelimumab Is Associated with Functional STK11 Mutations in Patients with Non-Small Cell Lung Cancer and Is Reversed by STAT3 Knockdown.

Mutations in the STK11 (LKB1) gene regulate resistance to PD-1/PD-L1 blockade. This study evaluated this association in patients with nonsquamous non-small cell lung cancer (NSCLC) enrolled in three phase I/II trials. STK11 mutations were associated with resistance to the anti-PD-L1 antibody durvalumab (alone/with the anti-CTLA4 antibody tremelimumab) independently of KRAS mutational status, highlighting STK11 as a potential driver of resistance to checkpoint blockade. Retrospective assessments of tumor tissue, whole blood, and serum revealed a unique immune phenotype in patients with STK11 mutations, with increased expression of markers associated with neutrophils (i.e., CXCL2, IL6), Th17 contexture (i.e., IL17A), and immune checkpoints. Associated changes were observed in the periphery. Reduction of STAT3 in the tumor microenvironment using an antisense oligonucleotide reversed immunotherapy resistance in preclinical STK11 knockout models. These results suggest that STK11 mutations may hinder response to checkpoint blockade through mechanisms including suppressive myeloid cell biology, which could be reversed by STAT3-targeted therapy. SIGNIFICANCE: Patients with nonsquamous STK11-mutant (STK11mut) NSCLC are less likely than STK11 wild-type (STK11wt) patients to respond to anti-PD-L1 ± anti-CTLA4 immunotherapies, and their tumors show increased expression of genes and cytokines that activate STAT3 signaling. Preclinically, STAT3 modulation reverses this resistance, suggesting STAT3-targeted agents as potential combination partners for immunotherapies in STK11mut NSCLC.This article is highlighted in the In This Issue feature, p. 2659.

Immune evasion by murine melanoma mediated through CC chemokine receptor-10.

Human melanoma cells frequently express CC chemokine receptor (CCR)10, a receptor whose ligand (CCL27) is constitutively produced by keratinocytes. Compared with B16 murine melanoma, cells rendered more immunogenic via overexpression of luciferase, B16 cells that overexpressed both luciferase and CCR10 resisted host immune responses and readily formed tumors. In vitro, exposure of tumor cells to CCL27 led to rapid activation of Akt, resistance to cell death induced by melanoma antigen-specific cytotoxic T cells, and phosphatidylinositol-3-kinase (PI3K)-dependent protection from apoptosis induced by Fas cross-linking. In vivo, cutaneous injection of neutralizing antibodies to endogenous CCL27 blocked growth of CCR10-expressing melanoma cells. We propose that CCR10 engagement by locally produced CCL27 allows melanoma cells to escape host immune antitumor killing mechanisms (possibly through activation of PI3K/Akt), thereby providing a means for tumor progression.

Relationship Between Progression-Free Survival, Objective Response Rate, and Overall Survival in Clinical Trials of PD-1/PD-L1 Immune Checkpoint Blockade: A Meta-Analysis.

PD-1/PD-L1 immune checkpoint blockade (ICB) has improved overall survival (OS) in solid tumor trials; however, parallel improvements in Response Evaluation Criteria in Solid Tumors (RECIST)-based surrogate end points, progression-free survival (PFS), and objective response rate (ORR), are not always observed. Here, we assess the surrogacy of PFS/ORR for OS with ICB therapy across advanced/metastatic tumors. In a trial-level analysis (N = 40 randomized trials), PFS, ORR, and OS treatment effects were correlated (Spearman's rho). In a patient-level analysis, data were extracted from available trials of durvalumab; the correlation of PFS and OS was evaluated (Bayesian normal-induced-copula-estimation model) and the ordinal association between objective response and OS hazard ratio (HR) were assessed with concordance index measures. High correlation was observed between PFS HR and OS HR in intention-to-treat (ITT; rho = 0.76) and PD-L1-enriched populations (0.74); modest (or limited) benefit in PFS was associated with meaningful improvement in OS. Moderate correlations were observed between ΔORR and OS HR: ITT, -0.63; PD-L1-enriched, -0.53. At the patient level, a positive association was observed between PFS and OS in non-small cell lung cancer (Kendall's Tau = 0.793; 95% confidence interval, 0.789-0.797), head and neck squamous cell carcinoma (0.794; 0.789-0.798), and bladder cancer (0.872; 0.869-0.875). Objective responders had significantly better OS (concordance index > 0.9) than nonresponders across these tumor types. Modest (or limited) improvement in RECIST-based end points did not rule out meaningful OS benefit, indicating they are imperfect surrogates and do not fully capture ICB clinical benefit. Therefore, caution is advised when basing early discontinuation of novel ICB agents on these end points.

Prognostic and Predictive Impact of Circulating Tumor DNA in Patients with Advanced Cancers Treated with Immune Checkpoint Blockade.

The utility of circulating tumor DNA (ctDNA) as a biomarker in patients with advanced cancers receiving immunotherapy is uncertain. We therefore analyzed pretreatment (n = 978) and on-treatment (n = 171) ctDNA samples across 16 advanced-stage tumor types from three phase I/II trials of durvalumab (± the anti-CTLA4 therapy tremelimumab). Higher pretreatment variant allele frequencies (VAF) were associated with poorer overall survival (OS) and other known prognostic factors, but not objective response, suggesting a prognostic role for patient outcomes. On-treatment reductions in VAF and lower on-treatment VAF were independently associated with longer progression-free survival and OS and increased objective response rate, but not prognostic variables, suggesting that on-treatment ctDNA dynamics are predictive of benefit from immune checkpoint blockade. Accordingly, we propose a concept of "molecular response" using ctDNA, incorporating both pretreatment and on-treatment VAF, that predicted long-term survival similarly to initial radiologic response while also permitting early differentiation of responders among patients with initially radiologically stable disease. SIGNIFICANCE: In a pan-cancer analysis of immune checkpoint blockade, pretreatment ctDNA levels appeared prognostic and on-treatment dynamics predictive. A "molecular response" metric identified long-term responders and adjudicated benefit among patients with initially radiologically stable disease. Changes in ctDNA may be more dynamic than radiographic changes and could complement existing trial endpoints.This article is highlighted in the In This Issue feature, p. 1775.

Final overall survival and safety update for durvalumab in third- or later-line advanced NSCLC: The phase II ATLANTIC study.

INTRODUCTION: In the phase II ATLANTIC study, durvalumab provided durable responses with acceptable tolerability in heavily pretreated patients with advanced NSCLC, across three independent patient cohorts defined by EGFR/ALK status and tumour PD-L1 expression. Preliminary overall survival (OS) data were encouraging. We now report final OS and updated safety data. METHODS: Patients with advanced NSCLC with disease progression following ≥2 previous systemic regimens received durvalumab 10 mg/kg every 2 weeks. The primary endpoint was objective response rate among patients with increased PD-L1 expression (defined as ≥25 % or ≥90 % of tumour cells [TCs], cohort-dependent). Secondary endpoints included OS and safety. RESULTS: 444 patients received durvalumab: 111 in Cohort 1 (EGFR+/ALK+), 265 in Cohort 2 (EGFR-/ALK-), and 68 in Cohort 3 (EGFR-/ALK-; TC ≥ 90 %). Median (95 % CI) OS was 13.3 months (6.3-24.5) in patients with EGFR+/ALK+ NSCLC with TC ≥ 25 %, 10.9 months (8.6-13.6) in patients with EGFR-/ALK- NSCLC with TC ≥ 25 %, and 13.2 months (5.9-not reached) in patients with EGFR-/ALK- NSCLC with TC ≥ 90 %. Median (95 % CI) OS was slightly shorter in patients with TC < 25 % (9.9 months [4.2-13.3] in patients with EGFR+/ALK+ NSCLC and 9.3 months [5.9-10.8] in those with EGFR-/ALK- NSCLC). Treatment-related adverse events of special interest occurred with similar incidences as reported previously. CONCLUSIONS: After additional follow-up, final OS data remain encouraging across all cohorts, further supporting the clinical activity of durvalumab in patients with heavily pretreated advanced NSCLC, including those with EGFR+/ALK+ tumours. There were no new safety signals.

Three-Year Overall Survival with Durvalumab after Chemoradiotherapy in Stage III NSCLC-Update from PACIFIC.

INTRODUCTION: In the phase 3 PACIFIC study of patients with unresectable stage III NSCLC without progression after chemoradiotherapy, durvalumab demonstrated significant improvements versus placebo in the primary end points of progression-free survival (hazard ratio [HR] = 0.52, 95% confidence interval [CI]: 0.42-65, p < 0.0001) and overall survival (OS) (HR = 0.68, 95% CI: 0.53-0.87, p = 0.00251), with manageable safety and no detrimental effect on patient-reported outcomes. Here, we report 3-year OS rates for all patients randomized in the PACIFIC study. METHODS: Patients, stratified by age, sex, and smoking history, were randomized (2:1) to receive durvalumab, 10 mg/kg intravenously every 2 weeks, or placebo for up to 12 months. OS was analyzed by using a stratified log-rank test in the intention-to-treat population. Medians and rates at 12, 24, and 36 months were estimated by the Kaplan-Meier method. RESULTS: As of January 31, 2019, 48.2% of patients had died (44.1% and 56.5% in the durvalumab and placebo groups, respectively). The median duration of follow-up was 33.3 months. The updated OS remained consistent with that previously reported (stratified HR = 0.69 [95% CI: 0.55-0.86]); the median OS was not reached with durvalumab but was 29.1 months with placebo. The 12-, 24- and 36-month OS rates with durvalumab and placebo were 83.1% versus 74.6%, 66.3% versus 55.3%, and 57.0% versus 43.5%, respectively. All secondary outcomes examined showed improvements consistent with previous analyses. CONCLUSIONS: Updated OS data from PACIFIC, including 3-year survival rates, demonstrate the long-term clinical benefit with durvalumab after chemoradiotherapy and further establish the PACIFIC regimen as the standard of care in this population.