Deciphering radiological stable disease to immune checkpoint inhibitors.

BACKGROUND: 'Stable disease (SD)' as per RECIST is a common but ambiguous outcome in patients receiving immune checkpoint inhibitors (ICIs). This study aimed to characterize SD and identify the subset of patients with SD who are benefiting from treatment. Understanding SD would facilitate drug development and improve precision in correlative research. PATIENTS AND METHODS: A systematic review was carried out to characterize SD in ICI trials. SD and objective response were compared to proliferation index using The Cancer Genome Atlas gene expression data. To identify a subgroup of SD with outcomes mirroring responders, we examined a discovery cohort of non-small-cell lung cancer (NSCLC). Serial cutpoints of two variables, % best overall response and progression-free survival (PFS), were tested to define a subgroup of patients with SD with similar survival as responders. Results were then tested in external validation cohorts. RESULTS: Among trials of ICIs (59 studies, 14 280 patients), SD ranged from 16% to 42% in different tumor types and was associated with disease-specific proliferation index (ρ = -0.75, P = 0.03), a proxy of tumor kinetics, rather than relative response to ICIs. In a discovery cohort of NSCLC [1220 patients, 313 (26%) with SD to ICIs], PFS ranged widely in SD (0.2-49 months, median 4.9 months). The subset with PFS >6 months and no tumor growth mirrored partial response (PR) minor (overall survival hazard ratio 1.0) and was proposed as the definition of SD responder. This definition was confirmed in two validation cohorts from trials of NSCLC treated with durvalumab and found to apply in tumor types treated with immunotherapy in which depth and duration of benefit were correlated. CONCLUSIONS: RECIST-defined SD to immunotherapy is common, heterogeneous, and may largely reflect tumor growth rate rather than ICI response. In patients with NSCLC and SD to ICIs, PFS >6 months and no tumor growth may be considered 'SD responders'. This definition may improve the efficiency of and insight derivable from clinical and translational research.

COVID-19 in patients with lung cancer.

BACKGROUND: Patients with lung cancers may have disproportionately severe coronavirus disease 2019 (COVID-19) outcomes. Understanding the patient-specific and cancer-specific features that impact the severity of COVID-19 may inform optimal cancer care during this pandemic. PATIENTS AND METHODS: We examined consecutive patients with lung cancer and confirmed diagnosis of COVID-19 (n = 102) at a single center from 12 March 2020 to 6 May 2020. Thresholds of severity were defined a priori as hospitalization, intensive care unit/intubation/do not intubate ([ICU/intubation/DNI] a composite metric of severe disease), or death. Recovery was defined as >14 days from COVID-19 test and >3 days since symptom resolution. Human leukocyte antigen (HLA) alleles were inferred from MSK-IMPACT (n = 46) and compared with controls with lung cancer and no known non-COVID-19 (n = 5166). RESULTS: COVID-19 was severe in patients with lung cancer (62% hospitalized, 25% died). Although severe, COVID-19 accounted for a minority of overall lung cancer deaths during the pandemic (11% overall). Determinants of COVID-19 severity were largely patient-specific features, including smoking status and chronic obstructive pulmonary disease [odds ratio for severe COVID-19 2.9, 95% confidence interval 1.07-9.44 comparing the median (23.5 pack-years) to never-smoker and 3.87, 95% confidence interval 1.35-9.68, respectively]. Cancer-specific features, including prior thoracic surgery/radiation and recent systemic therapies did not impact severity. Human leukocyte antigen supertypes were generally similar in mild or severe cases of COVID-19 compared with non-COVID-19 controls. Most patients recovered from COVID-19, including 25% patients initially requiring intubation. Among hospitalized patients, hydroxychloroquine did not improve COVID-19 outcomes. CONCLUSION: COVID-19 is associated with high burden of severity in patients with lung cancer. Patient-specific features, rather than cancer-specific features or treatments, are the greatest determinants of severity.

Severe immune-related adverse events are common with sequential PD-(L)1 blockade and osimertinib.

BACKGROUND: Concurrent programmed death-ligand-1 (PD-(L)1) plus osimertinib is associated with severe immune related adverse events (irAE) in epidermal growth factor receptor (EGFR)-mutant non-small-cell lung cancer (NSCLC). Now that PD-(L)1 inhibitors are routinely used as adjuvant and first-line treatments, sequential PD-(L)1 inhibition followed by osimertinib use may become more frequent and have unforeseen serious toxicity. METHODS: We identified patients with EGFR-mutant NSCLC who were treated with PD-(L)1 blockade and EGFR- tyrosine kinase inhibitors (TKIs), irrespective of drug or sequence of administration (total n = 126). Patient records were reviewed to identify severe (NCI-CTCAE v5.0 grades 3-4) toxicity. RESULTS: Fifteen percent [6 of 41, 95% confidence interval (CI) 7% to 29%] of all patients treated with sequential PD-(L)1 blockade followed later by osimertinib developed a severe irAE. Severe irAEs were most common among those who began osimertinib within 3 months of prior PD-(L)1 blockade (5 of 21, 24%, 95% CI 10% to 45%), as compared with >3-12 months (1 of 8, 13%, 95% CI 0% to 50%), >12 months (0 of 12, 0%, 95% CI 0% to 28%). By contrast, no severe irAEs were identified among patients treated with osimertinib followed by PD-(L)1 (0 of 29, 95% CI 0% to 14%) or PD-(L)1 followed by other EGFR-TKIs (afatinib or erlotinib, 0 of 27, 95% CI 0% to 15%). IrAEs occurred at a median onset of 20 days after osimertinib (range 14-167 days). All patients with irAEs required steroids and most required hospitalization. CONCLUSION: PD-(L)1 blockade followed by osimertinib is associated with severe irAE and is most frequent among patients who recently received PD-(L)1 blockade. No irAEs were observed when osimertinib preceded PD-(L)1 blockade or when PD-(L)1 was followed by other EGFR-TKIs. This association appears to be specific to osimertinib, as no severe irAEs occurred with administration of other EGFR-TKIs.

PD-L1 expression, tumor mutational burden, and response to immunotherapy in patients with MET exon 14 altered lung cancers.

Background: MET exon 14 alterations are actionable oncogenic drivers. Durable responses to MET inhibitors are observed in patients with advanced MET exon 14-altered lung cancers in prospective trials. In contrast, the activity of immunotherapy, PD-L1 expression and tumor mutational burden (TMB) of these tumors and are not well characterized. Patients and methods: Patients with MET exon 14-altered lung cancers of any stage treated at two academic institutions were identified. A review of clinicopathologic and molecular features, and an analysis of response to single-agent or combination immune checkpoint inhibition were conducted. PD-L1 immunohistochemistry was carried out and TMB was calculated by estimation from targeted next-generation sequencing panels. Results: We identified 147 patients with MET exon 14-altered lung cancers. PD-L1 expression of 0%, 1%-49%, and ≥50% were 37%, 22%, and 41%, respectively, in 111 evaluable tumor samples. The median TMB of MET exon 14-altered lung cancers was lower than that of unselected non-small-cell lung cancers (NSCLCs) in both independently evaluated cohorts: 3.8 versus 5.7 mutations/megabase (P < 0.001, n = 78 versus 1769, cohort A), and 7.3 versus 11.8 mutations/megabase (P < 0.001, n = 62 versus 1100, cohort B). There was no association between PD-L1 expression and TMB (Spearman's rho=0.18, P = 0.069). In response-evaluable patients (n = 24), the objective response rate was 17% (95% CI 6% to 36%) and the median progression-free survival was 1.9 months (95% CI 1.7-2.7). Responses were not enriched in tumors with PD-L1 expression ≥50% nor high TMB. Conclusion: A substantial proportion of MET exon 14-altered lung cancers express PD-L1, but the median TMB is lower compared with unselected NSCLCs. Occasional responses to PD-1 blockade can be achieved, but overall clinical efficacy is modest.

Phase 1 study of twice weekly pulse dose and daily low-dose erlotinib as initial treatment for patients with EGFR-mutant lung cancers.

Background: Patients with EGFR-mutant lung cancers treated with EGFR tyrosine kinase inhibitors (TKIs) develop clinical resistance, most commonly with acquisition of EGFR T790M. Evolutionary modeling suggests that a schedule of twice weekly pulse and daily low-dose erlotinib may delay emergence of EGFR T790M. Pulse dose erlotinib has superior central nervous system (CNS) penetration and may result in superior CNS disease control. Methods: We evaluated toxicity, pharmacokinetics, and efficacy of twice weekly pulse and daily low-dose erlotinib. We assessed six escalating pulse doses of erlotinib. Results: We enrolled 34 patients; 11 patients (32%) had brain metastases at study entry. We observed 3 dose-limiting toxicities in dose escalation: transaminitis, mucositis, and rash. The MTD was erlotinib 1200 mg days 1-2 and 50 mg days 3-7 weekly. The most frequent toxicities (any grade) were rash, diarrhea, nausea, fatigue, and mucositis. 1 complete and 24 partial responses were observed (74%, 95% CI 60-84%). Median progression-free survival was 9.9 months (95% CI 5.8-15.4 months). No patient had progression of an untreated CNS metastasis or developed a new CNS lesion while on study (0%, 95% CI 0-13%). Of the 18 patients with biopsies at progression, EGFR T790M was identified in 78% (95% CI 54-91%). Conclusion: This is the first clinical implementation of an anti-cancer TKI regimen combining pulse and daily low-dose administration. This evolutionary modeling-based dosing schedule was well-tolerated but did not improve progression-free survival or prevent emergence of EGFR T790M, likely due to insufficient peak serum concentrations of erlotinib. This dosing schedule prevented progression of untreated or any new central nervous system metastases in all patients.

Chemotherapy remains an essential element of personalized care for persons with lung cancers.

Molecularly targeted and immunotherapies have improved the care of patients with lung cancers. These successes have rallied calls to replace or avoid chemotherapy. Yet, even in this era of precision medicine and exciting advances, cytotoxic chemotherapies remain an essential component of lung cancer treatment. In the setting of locoregional disease, chemotherapy is the only systemic therapy thus far proven to enhance curability when combined with surgery or radiation. In the metastatic setting, chemotherapy can improve the length and quality of life in many patients. Chemotherapy remains the mainstay of care for individuals whose cancers with oncogenic drivers have acquired resistance to targeted agents. Chemotherapy also has the potential to modulate the immune system to enhance the effectiveness of immune checkpoint inhibitors. In this context, chemotherapy should be framed as a critical component of the armamentarium available for optimizing cancer care rather than an unfortunate anachronism. We examine the role of chemotherapy with precision medicine in the current care of patients with lung cancers, as well as opportunities for future integration in combinations with targeted agents, angiogenesis inhibitors, immunotherapies, and antibody drug conjugates.

A prospective study of total plasma cell-free DNA as a predictive biomarker for response to systemic therapy in patients with advanced non-small-cell lung cancers.

BACKGROUND: While previous studies have reported on the prognostic value of total plasma cell-free deoxyribonucleic acid (cfDNA) in lung cancers, few have prospectively evaluated its predictive value for systemic therapy response. PATIENTS AND METHODS: We conducted a prospective study to evaluate the association between changes in total cfDNA and radiologic response to systemic therapy in patients with stage IIIB/IV non-small-cell lung cancers (NSCLCs). Paired blood collections for cfDNA and computed tomography (CT) assessments by RECIST v1.0 were performed at baseline and 6-12 weeks after therapy initiation. Total cfDNA levels were measured in plasma using quantitative real-time polymerase chain reaction. Associations between changes in cfDNA and radiologic response, progression-free survival (PFS), and overall survival (OS) were measured using Kruskal-Wallis and Kaplan-Meier estimates. RESULTS: A total of 103 patients completed paired cfDNA and CT response assessments. Systemic therapy administered included cytotoxic chemotherapy in 57% (59/103), molecularly targeted therapy in 17% (17/103), and combination therapy in 26% (27/103). Median change in cfDNA from baseline to response assessment did not significantly differ by radiologic response categories of progression of disease, stable disease and partial response (P = 0.10). However, using radiologic response as continuous variable, there was a weak positive correlation between change in radiologic response and change in cfDNA (Spearman's correlation coefficient 0.21, P = 0.03). Baseline cfDNA levels were not associated with PFS [hazard ratio (HR) = 1.06, 95% confidence interval (CI) 0.93-1.20, P = 0.41] or OS (HR = 1.04, 95% CI 0.93-1.17, P = 0.51), neither were changes in cfDNA. CONCLUSIONS: In this large prospective study, changes in total cfDNA over time did not significantly predict radiologic response from systemic therapy in patients with advanced NSCLC. Pretreatment levels of total cfDNA were not prognostic of survival. Total cfDNA level is not a highly specific predictive biomarker and future investigations in cfDNA should focus on tumor-specific genomic alterations using expanded capabilities of next-generation sequencing.

Clinical outcomes with pemetrexed-based systemic therapies in RET-rearranged lung cancers.

BACKGROUND: RET rearrangements are targetable, oncogenic lung cancer drivers. While previous series have shown durable clinical benefit with pemetrexed-based therapies in ALK- and ROS1-rearranged lung cancers, the benefits of pemetrexed-based treatments in patients with RET-rearranged lung cancers relative to other genomic subsets have not previously been explored. PATIENTS AND METHODS: A retrospective review of patients with pathologically confirmed stage IIIB/IV lung adenocarcinomas and evidence of a RET, ROS1, or ALK rearrangement, or a KRAS mutation was conducted. Patients were eligible if they received treatment with pemetrexed alone or in combination. The primary outcome of progression-free survival (PFS), and secondary outcomes of overall response rate (ORR, RECIST v1.1), time to progression (TTP), and time to treatment discontinuation were compared between RET-rearranged and groups of ROS1-rearranged, ALK-rearranged, and KRAS-mutant lung cancers. RESULTS: We evaluated 104 patients. Patients with RET-rearranged lung cancers (n = 18) had a median PFS of 19 months [95% confidence interval (CI) 12-not reached (NR)] that was comparable with patients with ROS1- (23 months, 95% CI 14-NR, n = 10) and ALK-rearranged (19 months, 95% CI 15-36, n = 36) lung cancers, and significantly improved compared with patients with KRAS-mutant lung cancers (6 months, 95% CI 5-9, P < 0.001, n = 40). ORR (45%), median TTP (20 months, 95% CI 17-NR), and median time to treatment discontinuation (21 months, 95% CI 6-NR) in patients with RET-rearranged lung cancers were not significantly different compared with patients with ALK- and ROS1-rearranged lung cancers, and improved compared with patients with KRAS-mutant lung cancers. CONCLUSION: Durable benefits with pemetrexed-based therapies in RET-rearranged lung cancers are comparable with ALK- and ROS1-rearranged lung cancers. When selecting therapies for patients with RET-rearranged lung cancers, pemetrexed-containing regimens should be considered.

Epidermal growth factor receptor exon 20 insertions in advanced lung adenocarcinomas: Clinical outcomes and response to erlotinib.

BACKGROUND: Epidermal growth factor receptor (EGFR) exon 20 insertions (exon20ins) represent approximately 10% of EGFR-mutant lung adenocarcinomas, and are associated with resistance to EGFR tyrosine kinase inhibitors (TKIs). Clinical outcomes in comparison with patients with sensitizing EGFR mutations are not well established. METHODS: Patients with stage IV lung adenocarcinomas with EGFR exon20ins were identified through routine molecular testing. Clinicopathologic data were collected. Overall survival (OS) was measured from the diagnosis of stage IV disease, and in patients treated with EGFR TKIs, the time to progression (TTP) on erlotinib was measured. RESULTS: One thousand eight hundred and eighty-two patients with stage IV lung adenocarcinomas were identified: 46 patients had EGFR exon20ins (2%), and 258 patients had an EGFR exon 19 deletion (exon19del)/L858R point mutation (14%). Among 11 patients with lung adenocarcinomas with EGFR exon20ins who received erlotinib, 3 patients (27%) had a partial response (FQEA, 1; ASV, 1; and unknown variant, 1). TTP for patients with EGFR exon20ins and patients with EGFR exon19del/L858R on erlotinib were 3 and 12 months, respectively (P < .01). Responses to chemotherapy were similar for patients with lung adenocarcinomas with EGFR exon20ins and patients with lung adenocarcinomas with EGFR exon19del/L858R. Median OS from the diagnosis of stage IV disease for patients with EGFR exon20ins and patients with EGFR exon19del/L858R was 26 months (95% confidence interval, 19 months-not reached n = 46) and 31 months (95% confidence interval, 28-33 months; n = 258), respectively (P = .53). CONCLUSIONS: The majority of patients with advanced lung adenocarcinomas harboring EGFR exon20ins do not respond to EGFR TKI therapy. Standard chemotherapy should be used as first-line therapy. These patients have an OS similar to that of patients with sensitizing EGFR mutations. Individuals with certain variants such as FQEA and ASV may respond to erlotinib.

Targeting HER2 aberrations as actionable drivers in lung cancers: phase II trial of the pan-HER tyrosine kinase inhibitor dacomitinib in patients with HER2-mutant or amplified tumors.

BACKGROUND: HER2 mutations and amplifications have been identified as oncogenic drivers in lung cancers. Dacomitinib, an irreversible inhibitor of HER2, EGFR (HER1), and HER4 tyrosine kinases, has demonstrated activity in cell-line models with HER2 exon 20 insertions or amplifications. Here, we studied dacomitinib in patients with HER2-mutant or amplified lung cancers. PATIENTS AND METHODS: As a prespecified cohort of a phase II study, we included patients with stage IIIB/IV lung cancers with HER2 mutations or amplification. We gave oral dacomitinib at 30-45 mg daily in 28-day cycles. End points included partial response rate, overall survival, and toxicity. RESULTS: We enrolled 30 patients with HER2-mutant (n = 26, all in exon 20 including 25 insertions and 1 missense mutation) or HER2-amplified lung cancers (n = 4). Three of 26 patients with tumors harboring HER2 exon 20 mutations [12%; 95% confidence interval (CI) 2% to 30%] had partial responses lasting 3+, 11, and 14 months. No partial responses occurred in four patients with tumors with HER2 amplifications. The median overall survival was 9 months from the start of dacomitinib (95% CI 7-21 months) for patients with HER2 mutations and ranged from 5 to 22 months with amplifications. Treatment-related toxicities included diarrhea (90%; grade 3/4: 20%/3%), dermatitis (73%; grade 3/4: 3%/0%), and fatigue (57%; grade 3/4: 3%/0%). One patient died on study likely due to an interaction of dacomitinib with mirtazapine. CONCLUSIONS: Dacomitinib produced objective responses in patients with lung cancers with specific HER2 exon 20 insertions. This observation validates HER2 exon 20 insertions as actionable targets and justifies further study of HER2-targeted agents in specific HER2-driven lung cancers. CLINICALTRIALSGOV: NCT00818441.

Poor response to erlotinib in patients with tumors containing baseline EGFR T790M mutations found by routine clinical molecular testing.

BACKGROUND: EGFR T790M is the most common mutation associated with acquired resistance to EGFR tyrosine kinase inhibitors (TKIs). Baseline EGFR T790M mutations in EGFR TKI-naïve patients have been reported, but the frequency and their association with response to EGFR TKIs remain unclear. PATIENTS AND METHODS: The frequency of baseline EGFR T790M as detected by routine molecular genotyping was determined by reviewing clinical results obtained at our institution from 2009 to 2013. We also collected outcome data for treatment with EGFR TKIs. RESULTS: To define the incidence of EGFR T790M, we reviewed 2774 sequentially tested patients with lung cancer who underwent molecular testing using a mass spectrometry-based assay, and 11 (0.5%) had baseline EGFR T790M. Compiling results from several molecular techniques, we observed EGFR T790M in tumors from 20 patients who had not previously been treated with an EGFR TKI. In all cases, EGFR T790M occurred concurrently with another EGFR mutation, L858R (80%, 16/20), or exon 19 deletion (20%, 4/20). Two percent of all pre-treatment EGFR-mutant lung cancers harbored an EGFR T790M mutation. Thirteen patients received erlotinib monotherapy as treatment for metastatic disease. The response rate was 8% (1/13, 95% confidence interval 0%-35%). For the patients who received erlotinib, the median progression-free survival was 2 months and the median overall survival was 16 months. CONCLUSIONS: De novo EGFR T790M mutations are rare (<1%) when identified by standard sensitivity methods. TKI therapy for patients with baseline EGFR T790M detected by standard molecular analysis has limited benefit.

Gemcitabine nephrotoxicity and hemolytic uremic syndrome: report of 29 cases from a single institution.

BACKGROUND: Gemcitabine is used in a variety of advanced malignancies. Hemolytic uremic syndrome has been reported as a side effect. METHODS: we reviewed medical records of 29 patients with gemcitabine nephrotoxicity. RESULTS: The median cumulative dose of gemcitabine was 22 g/m2 (4 - 81) given over 7.5 months (2 - 34). Prior chemotherapy with mitomycin had been given to 9 patients, and in 4 the hemolytic uremic syndrome was particularly severe and appeared shortly after gemcitabine initiation. All patients had renal insufficiency. Microhematuria and proteinuria were present in 27 patients and red blood cell casts were seen in 8. Renal biopsies in 4 patients showed thrombotic microangiopathy. Worsening or new-onset hypertension was seen in 26 patients. Edema, shortness of breath and congestive heart failure were present in 21, 15 and 7 patients, respectively. All had anemia, thrombocytopenia and elevated serum lactate dehydrogenase. Haptoglobin was low in 23 of the 26 patients who had it measured. Schistocytes were present in 21 of the 24 patients who had blood smear reviewed. Gemcitabine was discontinued once hemolytic uremic syndrome was recognized. Full or partial recovery of renal function occurred in 19 patients. 7 patients progressed to end-stage renal disease and 3 patients developed chronic renal failure. CONCLUSIONS: Gemcitabine nephrotoxicity presents as new-onset renal disease with associated hypertension, thrombocytopenia and microangiopathic hemolytic anemia. Prior chemotherapy with mitomycin, especially when given in close proximity, may be synergistic. A high index of suspicion is essential to make an early diagnosis. Stopping gemcitabine improves the outcome.

Phase II trials of the serotonin antagonist GR38032F for the control of vomiting caused by cisplatin.

Three phase II studies of the serotonin antagonist GR38032F were conducted. In trial 1, 20 patients given initial chemotherapy with cisplatin at doses greater than or equal to 100 mg/m2 were randomized to receive three GR38032F doses (0.18 mg/kg) on an every-2-hour or every-4-hour schedule. In trial 2, eight similar patients were given three 0.04-mg/kg doses every 2 hours. In trial 3, 12 previously treated patients receiving cisplatin at 20-25 mg/m2 on 4 or 5 consecutive days each received three daily GR38032F doses (0.15 mg/kg) every 2 hours. In trial 1, 35% of the patients had no emesis [95% confidence interval (CI), 16%-58%] and 55% had one or two emetic episodes (95% CI, 32%-76%). Results were similar between the every-2-hour and every-4-hour schedules. In trial 2, only one of eight patients (13%) had no vomiting (95% CI, 1%-50%). In trial 3, in which previously treated patients were studied, complete control ranged from 75% on day 1 to 33% on day 3. Mild sedation, headache, and transient elevations of serum SGOT (AST) were observed. No extrapyramidal symptoms occurred. A dose of 0.15-0.18 mg/kg every 2 hours for three iv doses is recommended. Further comparison and combination studies of GR38032F are warranted.

Constitutive variability in the pharmacokinetics of the natural retinoid, all-trans-retinoic acid, and its modulation by ketoconazole.

BACKGROUND: All-trans-retinoic acid (all-trans RA) induces complete remission in most patients with acute promyelocytic leukemia (APL). However, continuous oral dosing results in progressive decline in plasma drug concentrations, which is associated with relapse and resistance to this retinoid. We speculated that the decline in drug levels, indicating acquired resistance, resulted partly from inducible cytochrome-P450 oxidative enzymes, which can catabolize all-trans RA. PURPOSE: We studied the clinical pharmacology of all-trans RA in cancer patients to determine possible mechanisms of acquired resistance and evaluated the potential for reversal by ketoconazole, an inhibitor of cytochrome-P450 oxidative enzymes. METHODS: Serial plasma samples were obtained from 54 patients with APL or advanced lung cancer after a single oral dose of all-trans RA (45 mg/m2). In the 34 patients with advanced lung cancer, all-trans RA (45 mg/m2) was administered twice daily for 4 weeks, and, on days 2, 28, and 29, serial plasma samples were again obtained after a single 45-mg/m2 dose. One hour prior to drug administration on days 2 and 29, a single oral dose (200-1200 mg) of ketoconazole was administered. Endogenous plasma concentrations of all-trans RA and 13-cis-retinoic acid were measured in a subset of these patients and in 11 with early-stage lung cancer. RESULTS: The mean area under the curve for plasma drug concentration times time (AUC) for all-trans RA on day 1 varied substantially among patients. Compared with patients with APL, the 28 patients with advanced lung cancer who completed therapy demonstrated significantly lower AUC levels on day 1 (P = .06); a subgroup with levels less than 300 ng/mL per hour on day 1 had lower endogenous plasma all-trans RA concentrations than patients with APL or early-stage lung cancer or 14 normal subjects. Following continuous oral treatment, the mean day 28 AUC for all-trans RA was significantly lower than that on day 1 (213 ng/mL per hour versus 467 ng/mL per hour; P < .01), a decline significantly attenuated by ketoconazole, which increased the mean plasma all-trans RA AUC on day 29 to 375 ng/mL per hour (P < .01). CONCLUSION: Reported variability for the pharmacokinetics of all-trans RA may result from disease-related or population-based differences in basal catabolic rates influenced by genetic or environmental factors. However, the pattern of inducible catabolism of all-trans RA is not disease specific. Ketoconazole attenuates this accelerated catabolism, suggesting that oxidation by cytochrome-P450 enzymes is an important pathway for both constitutive and induced pathways of all-trans RA metabolism.

Phase I clinical and pharmacological study of chloroquinoxaline sulfonamide.

Chloroquinoxaline sulfonamide (CQS) is a halogenated heterocyclic sulfanilamide identified by the in vitro human tumor colony-forming assay as an active agent in a variety of human solid tumors. In this phase I study, 182 courses of CQS were administered intravenously every 28 days to 88 patients at doses ranging from 18 to 4870 mg/m2. Hypoglycemia associated with hyperinsulinemia was the dose-limiting adverse effect at 4870 mg/m2. Supraventricular tachyarrhythmias were observed at doses > 4000 mg/m2. Less common reactions included infusion site phlebitis, nausea, anemia, alopecia, perioral numbness, and diarrhea. Cumulative toxicity was not observed. Minor objective antitumor responses were noted in 7 patients; 6 of the 7 responses occurred in patients with non-small cell lung cancer. Results of pharmacokinetic studies were consistent with the preclinical observations that CQS is highly bound to plasma protein. Plasma elimination followed a two-compartment model; the mean t 1/2 alpha was 2.7 +/- 0.3 h and the t 1/2 beta was 52 +/- 6 h (+/- SE). The total body clearance and the volume of distribution at steady state of CQS both increased with the dose (distribution at steady state, 3.7-10.5 liter/m2; total body clearance, 53-264 ml/h/m2 for doses of 18-4060 mg/m2) and may reflect saturation of the protein binding and "free" drug clearance. Although inactive against common animal tumors in preclinical screening systems both in vitro and in vivo, CQS has demonstrated definite activity in the human tumor stem cell colony-forming assays, as well as modest anticancer activity in this phase I study in patients with advanced solid tumors. The pharmacokinetic results and the limiting effect of transient hypoglycemia suggest that considerably higher cumulative doses of CQS could be administered using a more frequent dosing schedule.

Metabolic phenotypes of retinoic acid and the risk of lung cancer.

The metabolic activity of cytochrome P-450 enzymes has been associated with an increased risk of developing lung cancer. We found previously that all-trans retinoic acid is catabolized by these oxidative enzymes, and that an inhibitor of this system discriminated between two populations of lung cancer patients. We examined the association between this metabolic phenotype and the risk of lung cancer in 85 subjects. The area under the plasma concentration x time curve (AUC) was calculated after a single oral dose of all-trans retinoic acid (45 mg/m2). The mean AUC for patients who had either squamous or large cell carcinomas was significantly lower than that of patients with adenocarcinomas (P = 0.0001) or control subjects (P = 0.01). Individuals with an AUC < 250 ng x h/ml had a greater likelihood of having squamous or large cell carcinoma (odds ratio = 5.93). This study suggests that the "rapid" catabolism of all-trans retinoic acid is linked to an increased risk of squamous or large cell cancers of the lung.

Phase I trial and clinical pharmacological evaluation of 10-ethyl-10-deazaaminopterin in adult patients with advanced cancer.

10-Ethyl-10-deazaaminopterin (10-EDAM) is an analogue of methotrexate with improved preclinical anticancer activity, more selective entry, and greater conversion to polyglutamate forms in neoplastic cells. In this Phase I trial, we have treated 62 adults with advanced solid tumors, giving 10-EDAM i.v. on either a weekly x 3 schedule (35 patients) or a weekly schedule (27 patients). The dosage levels ranged from 5 to 120 mg/m2. The toxicity observed with 10-EDAM was qualitatively similar to that of methotrexate. Oral mucositis was the dose-limiting toxicity; diarrhea, skin rash, leukopenia, thrombocytopenia, and mild elevations of serum glutamic-oxaloacetic transaminase, prothrombin, and partial thromboplastin times were also observed, but were not dose limiting. A weekly dosage of 80 mg/m2 with escalation or attenuation in accordance with patient tolerance, or 100 mg/m2 weekly for 3 weeks, followed by a 2-week "rest period" are recommended for Phase II assessment. 10-EDAM produced partial remissions in three patients with non-small cell lung cancer and one patient with breast cancer lasting 6, 40+, 26+, and 15 months, respectively. Pharmacokinetic studies carried out at the 5, 30, and 100 mg/m2 dosage levels demonstrated the drug to have a triphasic disappearance from plasma. Elimination was independent of dose over the range tested, with mean plasma half-lives of: alpha = 12.9 min, beta = 1.5 h, and gamma = 11.9 h. Cumulative urinary excretion of the drug ranged from 13 to 55% of the administered dose (mean = 33%); 88% of the urinary drug appeared within the first 4 h following drug administration. The pharmacokinetic behavior of the first and second weekly dosages were consistent within a given patient. The metabolites 7-hydroxy-10-EDAM, and 10-ethyl-10-deaza-2,4-diamino-pteroic acid were demonstrated in the plasma and urine of treated patients. In studies of tissue homogenates from two patients with skin metastases, more extensive retention of the drug and of its polyglutamates was observed in the breast cancer metastases than in the metastases from a kidney cancer or in normal skin.

Comparison of CT volumetric measurement with RECIST response in patients with lung cancer.

PURPOSE: To examine the correlations between uni-dimensional RECIST and volumetric measurements in patients with lung adenocarcinoma and to assess their association with overall survival (OS) and progression-free survival (PFS). MATERIALS AND METHODS: In this study of patients receiving chemotherapy for lung cancer in the setting of a clinical trial, response was prospectively evaluated using RECIST 1.0. Retrospectively, volumetric measurements were recorded and response was assessed by two different volumetric methods at each followup CT scan using a semi-automated segmentation algorithm. We subsequently evaluated the correlation between the uni-dimensional RECIST measurements and the volumetric measurements and performed landmark analyses for OS and PFS at the completion of the first and second follow-ups. Kaplan-Meier curves together with log-rank tests were used to evaluate the association between the different response criteria and patient outcome. RESULTS: Forty-two patients had CT scans at baseline, after the first follow up scan and second followup scan, and then every 8 weeks. The uni-dimensional RECIST measurements and volumetric measurements were strongly correlated, with a Spearman correlation coefficient (ρ) of 0.853 at baseline, ρ=0.861 at the first followup, ρ=0.843 at the 2nd followup, and ρ=0.887 overall between-subject. On first follow-up CT, partial responders and non responders as assessed by an "ellipsoid" volumetric criteria showed a significant difference in OS (p=0.008, 1-year OS of 70% for partial responders and 46% for non responders). There was no difference between the groups when assessed by RECIST criteria on first follow-up CT (p=0.841, 1-year OS rate of 64% for partial responders and 64% for non responders). CONCLUSION: Volumetric response on first follow-up CT may better predict OS than RECIST response. CLINICAL RELEVANCE STATEMENT: Assessment of tumor size and response is of utmost importance in clinical trials. Volumetric measurements may help to better predict OS than uni-dimensional RECIST criteria.

Dose-ranging evaluation of the serotonin antagonist GR-C507/75 (GR38032F) when used as an antiemetic in patients receiving anticancer chemotherapy.

GR-C507/75 (GR38032F) antagonizes the 5-HT3 (serotonin) receptor and prevents cisplatin-induced emesis in animals. In this dose-ranging trial, 44 patients with cancer receiving chemotherapy known to produce nausea and vomiting (including cisplatin, cyclophosphamide, and doxorubicin) received three intravenous (IV) infusions of GR-C507/75 every two hours beginning 30 minutes before chemotherapy. Ten dosage levels were explored, ranging from 0.04 mg/kg to 0.35 mg/kg in each of the three infusions. Toxicities were mild and included sedation, dizziness, headache, transient elevations of SGOT or alanine aminotransferase (ALT), and dry mouth. No akathisia or acute dystonic reactions were observed. Antiemetic effects were seen in patients receiving cisplatin at 120 mg/m2. GR-C507/75 can be safely administered on this schedule at IV dosages up to 0.35 mg/kg in patients receiving chemotherapy. Further studies of this agent at higher dosages and by different schedules are appropriate.

Control of chemotherapy-induced diarrhea with the synthetic enkephalin BW942C: a randomized trial with placebo in patients receiving cisplatin.

Diarrhea commonly occurs following the administration of cisplatin. BW942C, a pentapeptide, is a synthetic enkephalin shown to control castor oil-induced and traveler's diarrhea. To assess the safety and efficacy of BW942C in controlling diarrhea caused by cisplatin, 30 adults with lung cancer who had already experienced diarrhea (three or more loose bowel movements) during the 24-hour period following a prior cisplatin administration were randomized to receive either BW942C or placebo during the next cisplatin course. All patients received a concomitant antiemetic regimen including metoclopramide, dexamethasone, and lorazepam during all courses. Patients administered BW942C experienced less diarrhea (27% v 67%, P = .02). Twenty-seven percent of patients given the pentapeptide had loose bowel movements as opposed to 93% who received placebo (P = .0002). There were no significant differences in the incidence and degree of vomiting and other treatment-related side effects observed between the placebo and treatment groups. We conclude that oral BW942C is more effective than placebo in controlling diarrhea following cisplatin chemotherapy.