Corticosteroid-Refractory Myositis After Dual BRAF and MEK Inhibition in a Patient with BRAF V600E-Mutant Metastatic Intrahepatic Cholangiocarcinoma

Intrahepatic cholangiocarcinoma is a rare malignancy, which is rich in actionable alterations. Genomic aberrations in the mitogen-activated protein kinase (MAPK) pathway are common, and BRAF exon 15 p.V600E mutations are present in 5–7% of biliary tract cancers (BTC). Dual inhibition of BRAF and MEK has been established for BRAF-mutated melanoma and lung cancer, and recent basket trials have shown efficacy of this combination in BRAF V600E-mutant BTCs. Here, we report on a patient with BRAF exon 15 p.V600E mutant metastatic intrahepatic cholangiocarcinoma who was started on BRAF and MEK inhibition with vemurafenib and combimetinib. Shortly thereafter, he developed debilitating myositis, which was refractory to corticosteroids, requiring therapeutic plasma exchange and intravenous immunoglobulin. We also review BRAF as a target in BTCs, relevant clinical trials, and adverse events associated with BRAF and MEK inhibition.

The CTSA University of Texas Health Science Center (UTHSC) Northeast-Tyler and Rio Grande Valley Success Story: How Rural, Underserved Academic Communities Rapidly Built a Robust Engine for Collaborative COVID-19 Clinical Research

In 2018, The University of Texas Health Science Center-Tyler and University of Texas Rio Grande Valley were invited to develop clinical research units for an existing Clinical and Translational Science Award (CTSA) consortium with the objective to equip medically underserved, economically disadvantaged communities and subsequently to deploy COVID-19 clinical trials in response to a public health emergency.

Selinexor in combination with standard chemotherapy in patients with advanced or metastatic solid tumors

Selinexor, an oral selective inhibitor of nuclear export (SINE), was demonstrated to hinder the DNA damage repair (DDR) system by reducing DDR proteins while enhancing the killing of cancer cells by DDR-based therapeutics in vivo studies. In this single-center, multi-arm phase 1b study, selinexor with carboplatin, doxorubicin and cyclophosphamide (DC), irinotecan with fluorouracil and folinic acid (FOLFIRI), irinotecan, and capecitabine and oxaliplatin (XELOX), were employed as separate parallel arms. Eligible patients have relapsed/ metastatic refractory solid tumors following standard therapy or addition of selinexor to systemic therapy was appropriate. Nineteen patients were treated in the 5 arms. Tumor types included were colorectal (n  = 3), breast (n  = 3), neuroendocrine (n  = 2), ovarian (n  = 2), and pancreas cancers (n  = 2). All patients developed one treatment-related adverse events (TRAE). The most prevalent TRAE were thrombocytopenia (84%), nausea (68%), leukopenia (68%), neutropenia (63%), and fatigue (58%). The common grade 3/4 TRAE were neutropenia (42%), leukopenia (26%), and hyponatremia (21%). Three patients had dose-limiting toxicities (DLT) in 3 separate arms. Fourteen patients were evaluable for response. Although no patients achieved complete or partial response (CR or PR), seven patients attained stable disease (SD). Disease control rate (DCR) was 14%. The combination of oral selinexor with different standard chemotherapies showed limited clinical activity despite toxicity and DLT prevented further dose escalation. Optimizing supportive care, the utility of growth factors, and aggressive measures on antiemetics strategies remain tangible.

Trial registration ClinicalTrials.gov Identifier: NCT02419495. Registered 14 April 2015, https://clinicaltrials.gov/ct2/show/NCT02419495). Sponsor(s): Karyopharm Therapeutics

300. Long COVID in Cancer Patients: Preponderance of Symptoms in Majority of Patients Over Long Time Period

Background

An increasing number of observational studies have reported the persistence of symptoms following recovery from acute COVID-19 disease. The long-term consequences of COVID-19 are not fully understood and there is no clear consensus on the definition of post-acute sequelae of SARS-CoV-2 infection (PASC). The reported prevalence of PASC widely varies from 10% up to 87%. The purpose of this study is to assess PASC in cancer patients following acute COVID-19 recovery.

Methods

We assessed cancer patients at MD Anderson Cancer Center who were diagnosed with COVID-19 disease between March 1, 2020 and Sept 1, 2020. Using patient questionnaires and medical chart reviews we followed these patients from March 2020 till May 2021. Patient questionnaires were sent out remotely daily for 14 days after COVID-19 diagnosis then weekly for 3 months, and then monthly thereafter. Chart reviews were conducted for each patient hospital re-admission and emergency department visit. These admissions were classified as either COVID-19 related or non-related. The persistence or emergence of new COVID19-related symptoms were captured at each COVID-19 related admission.

Results

We included 312 cancer patients with a median age of 57 years (18-86). The majority of patients had solid tumors (75%). Of the 312 patients, 188 (60%) reported long COVID-19 symptoms with a median duration of 7 months and up to 14 months after COVID-19 diagnosis. The most common symptoms reported included fatigue (82%), sleep disturbances (78%), myalgias (67%) and gastrointestinal symptoms (61%), followed by headache, altered smell or taste, dyspnea (47%) and cough (46%). A higher number of females reported a persistence of symptoms compared to males (63% vs 37%; p=0.036). Cancer type, neutropenia, lymphocytopenia, and hospital admission during acute COVID-19 disease were comparable in both groups and did not seem to contribute to a higher number of long-COVID-19 patients in our study group.

Conclusion

Long-COVID occurs in 60% of cancer patients and may persist up to 14 months after acute illness. The most common symptoms are fatigue, sleep disturbance, myalgia and gastro-intestinal symptoms.

Disclosures

Fareed Khawaja, MBBS, Eurofins Viracor (Research Grant or Support)

Compliance with dietary guidelines and its relationship with symptoms and clinical outcomes in patients with advanced cancer in early-phase oncology clinical trials

199

Background: We examined compliance with the Dietary Guidelines for Americans and its association with symptom burden and clinical outcomes in patients with advanced cancer in early-phase clinical trials testing novel immunotherapeutic and targeted agents. Methods: Patients starting an early-phase clinical trial (ECOG-PS = 0-1) were recruited into a prospective, longitudinal design with assessments at baseline and at the end of Cycle 1. Diet and symptom burden were assessed using the validated National Cancer Institute Diet History Questionnaire (NCI-DHQ) and the MD Anderson Symptom Inventory, respectively. Compliance with the Dietary Guidelines for Americans recommendations was measured via the Healthy Eating Index (HEI) (a measure of dietary intake per total energy), computed from NCI-DHQ food group and nutrient scores; higher HEI scores indicate greater compliance with dietary guidance recommendations (possible range = 0–100). Statistical tests included Spearman rank correlations (rho), and Cox proportional hazards models. Results: Among early-phase clinical trial patients [N = 40; 50% female; 80% Non-Hispanic White; 80% ECOG = 1; 36% on trials including an immunotherapeutic agent and 64% on targeted therapy trials; mean age = 55y; mean BMI = 28], mean HEI was 69, compared to 59 for the US general population. The proportion of phase I clinical trial patients who met adequacy guidelines were 80% for whole fruit, 73% for total protein foods, 55% for seafood and plant proteins, 55% for total fruit, 50% for greens and beans, 28% for total vegetables, 15% for fatty acids [(PUFAs + MUFAs)/SFAs ≥2.5], 13% for dairy, and 0% for whole grains. The proportion of patients who met moderation guidelines were 28% for refined grains, 28% for added sugar, 13% for saturated fat, and 0% for sodium. Female patients had higher HEI scores than male patients (73 vs. 65, P = 0.004). Patients who were normal weight (BMI < 25) had higher scores for meeting the moderation in sugar intake guideline than overweight patients (BMI≥25) (7.7 vs. 5.5, P = 0.031). Higher intakes of cooked lean meat from beef, pork, veal, lamb, and game were linked to prolonged overall survival (HR = 0.5, 95%CI = 0.26, 0.96, P = 0.039). In immunotherapy patients, greater compliance with seafood and plant protein recommendations was associated with less fatigue at end of Cycle 1 (rho = -0.7, P = 0.008); in targeted therapy patients, higher glycemic load was associated with worse pain (rho = 0.7, P = 0.004). Conclusions: Diets of these early-phase clinical trial patients overall were congruent with recommendations in the Dietary Guidelines for Americans. However, increasing intakes of whole grains and reducing sodium intakes may be useful dietary goals for this population. Also, dietary factors may influence symptoms, such as fatigue and pain, in early-phase clinical trial patients with advanced cancer.

Selinexor in combination with topotecan in patients with advanced or metastatic solid tumors: Results of an open-label, single-center, multi-arm phase Ib study

Background Selinexor, a first-in-class, oral selective inhibitor of nuclear export (SINE) compound inhibits Exportin-1(XPO1), had demonstrated synergistic activity with many chemotherapies and conferred in vivo antitumor efficacy in hematologic as well as solid tumors. Methods This open-label, single-center, multi-arm phase 1b study used a standard 3 + 3 design and a "basket type" expansion. Selinexor with intravenous topotecan was given in one of the 13 parallel arms. Patients with advanced or metastatic relapsed/refractory solid tumors following prior systemic therapy, or in whom the addition of selinexor to standard chemotherapy deemed appropriate, were eligible. Results Fourteen patients with the median age of 61 years (range, 22-68years) were treated, and the most common cancer types were gynecological cancers; ovarian (n = 5), endometrial (n = 2), and 1 each with fallopian tube and vaginal cancers. Of the 14 patients treated, 12 (86 %) had at least one treatment-related adverse event (TRAE). The most common TRAEs were anemia (71 %), thrombocytopenia (57 %), hyponatremia (57 %), vomiting (57 %), fatigue (50 %), nausea (50 %), and neutropenia (36 %). Two patients had dose limiting toxicities. One patient dosed at selinexor 80 mg had grade 3 nausea and vomiting and one patient dosed at selinexor 60 mg experienced grade 4 neutropenia and thrombocytopenia. Of the 13 efficacy evaluable patients, one (8 %) with endometrial cancer achieved unconfirmed partial response (uPR) and the time-to-treatment failure (TTF) was 48 weeks, whereas 6 of the 13 (46 %) patients had stable disease (SD) contributing to the clinical benefit rate of 46 %. The median TTF for all patients was 9 weeks (range, 2-48weeks). Conclusions Once weekly selinexor in combination with topotecan was viable and showed some preliminary tumor efficacy. The recommend phase 2 dose of selinexor was 60 mg once weekly in combination with IV topotecan.Trial registration: NCT02419495. Registered 14 April 2015, https://clinicaltrials.gov/ct2/show/NCT02419495.

Selinexor in combination with carboplatin and paclitaxel in patients with advanced solid tumors: Results of a single-center, multi-arm phase Ib study

Background. Carboplatin and paclitaxel (CT) is one of the standard chemotherapy regimens used in various tumor types. Preclinical models have suggested that selinexor, a first-in-class oral potent selective inhibitor of nuclear export Exportin-1, and CT exerts antitumor activity in multiple malignancies. Methods. This was a single-center, multi-arm phase Ib study utilizing a “basket type” expansion. CT and selinexor was employed as one of the 13 parallel arms. Advanced relapsed/refractory solid tumors following standard therapy or where the addition of selinexor to standard regimens deemed appropriate, were eligible. Results. Of 13 patients treated, 12 patients were evaluable for response. The most common cancers were breast (n = 4), esophageal (n = 2), ovarian (n = 2) and non-small cell lung cancers (n = 2). All 13 patients had at least one treatment-related adverse events (TRAEs) and the most common were neutropenia (85%), leukopenia (85%), thrombocytopenia (85%), anemia (69%), nausea (54%), vomiting (46%), and fatigue (46%). One patient at 60 mg QW experienced DLT with grade 3 nausea and vomiting lasting 3 days. Unconfirmed partial response (uPR) was observed in 3 patients; one patient each with esophageal, breast, and ovarian cancer. One patient with esophageal adenocarcinoma had confirmed PR, however, was discontinued from the study due to clinical progression. Five patients achieved stable disease (SD). Disease control rate was 8%. Majority of patients (77%), including two patients who had uPR, had prior exposure to carboplatin and/or paclitaxel. Time-to-treatment failure (TTF) ranged from 1 to 153 weeks. Conclusion. The RP2D of selinexor was 60 mg QW in combination with CT. The combination conferred viable clinical activity with durable objective responses which should further be explored in tumor types for which CT is used as standard of care. Trial information. ClinicalTrials.gov Identifier: NCT02419495. Sponsor(s): Karyopharm Therapeutics. (Trial registration: NCT02419495. Registered 14 April 2015, https://clinicaltrials.gov/ct2/show/NCT02419495).

Supportive care for the prevention of nausea, vomiting and anorexia in a phase 1B study of selinexor in advanced cancer patients: an exploratory study

INTRODUCTION

Clinical observations of cancer patients treated with selinexor have reported high incidence of nausea and anorexia. The study objective was to investigate the adoption of prophylactic olanzapine for the prevention of nausea, vomiting and anorexia in cancer patients receiving selinexor and standard chemotherapy.

METHODS

We retrospectively reviewed supportive care interventions in patients receiving selinexor and recorded frequency of adverse events (NCI-CTAE). Association between categorical variables were analyzed using Fisher's exact tests; repeated measures analysis was performed to assess weight changes over time.

RESULTS

Of 124 evaluable patients, 83 (66.9%) were female, 93 were white (75.0%), and the most common cancer was ovarian (N = 30, 24.2%). One hundred and four patients (83.9%) received olanzapine, of which 93 (89.4%) were prophylactically treated, the majority (86.5%) receiving low 2.5 mg daily dose. Other anti-emetics included ondansetron in 90 patients (72.6%), dexamethasone prescribed in 50 patients (40.3%) and metoclopramide in 49 patients (39.5%), while aprepitant/fosaprepitant (N = 2, 1.6%) were prescribed infrequently. Cancer patients receiving prophylactic olanzapine (N = 93) compared to patients who never received olanzapine (N = 20) had more Grade 1 + anorexia (31.2% vs 20.0%), less nausea (53.8% vs 70.0%), less vomiting (33.3% vs 40.0%), and increased hyperglycemia (29.0% vs 10.0%), but differences were non-statistically significant. In addition, there was minimal weight loss over time in both groups and no statistically significant differences in weight loss between groups.

CONCLUSION

Prophylactic olanzapine decreased nausea, vomiting and maintained weight over 3 months but did not prevent anorexia in patients receiving selinexor and chemotherapy. Low dose olanzapine was well tolerated but associated with hyperglycemia.

PIK3CA mutations in plasma circulating tumor DNA predict survival and treatment outcomes in patients with advanced cancers

Background

Oncogenic mutations in PIK3CA are prevalent in diverse cancers and can be targeted with inhibitors of the phosphoinositide-3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) pathway. Analysis of circulating tumor DNA (ctDNA) provides a minimally invasive approach to detect clinically actionable PIK3CA mutations.

Patients and methods

We analyzed PIK3CA hotspot mutation frequency by droplet digital PCR (QX 200; BioRad) using 16 ng of unamplified plasma-derived cell-free DNA from 68 patients with advanced solid tumors (breast cancer, n = 41; colorectal cancer, n = 13; other tumor types, n = 14). Results quantified as variant allele frequencies (VAFs) were compared with previous testing of archival tumor tissue and with patient outcomes.

Results

Of 68 patients, 58 (85%) had PIK3CA mutations in tumor tissue and 43 (74%) PIK3CA mutations in ctDNA with an overall concordance of 72% (49/68, κ = 0.38). In a subset analysis, which excluded samples from 26 patients known not to have disease progression at the time of sample collection, we found an overall concordance of 91% (38/42; κ = 0.74). PIK3CA-mutated ctDNA VAF of ≤8.5% (5% trimmed mean) showed a longer median survival compared with patients with a higher VAF (15.9 versus 9.4 months; 95% confidence interval 6.7-17.1 months; P = 0.014). Longitudinal analysis of ctDNA in 18 patients with serial plasma collections (range 2-22 time points, median 5) showed that those with a decrease in PIK3CA VAF had a longer time to treatment failure (TTF) compared with patients with an increase or no change (10.7 versus 2.6 months; P = 0.048).

Conclusions

Detection of PIK3CA mutations in ctDNA is concordant with testing of archival tumor tissue. Low quantity of PIK3CA-mutant ctDNA is associated with longer survival and a decrease in PIK3CA-mutant ctDNA on therapy is associated with longer TTF.

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Testing for PIK3CA mutations in ctDNA is concordant with testing of tumor tissue.

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High PIK3CA-mutant abundance in ctDNA was associated with shorter survival.

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Increasing PIK3CA-mutant abundance in serial blood samples was associated with shorter TTF.

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Longitudinal monitoring of PIK3CA-mutant ctDNA tracked with cancer clinical course.

A phase i study of ixazomib and erlotinib in patients with advanced solid tumors

BACKGROUND

Preclinical studies have shown that the combined inhibition of EGFR and NF-kB pathways to target the RalB/TBK1 pathway led to synergistic antitumor activity. Based on this rationale, we conducted a Phase I dose-escalation study combining the EGFR inhibitor erlotinib with the NF-kB inhibitor ixazomib in advanced solid tumors. Patients and methods. Patients with advanced solid tumors were eligible. The bayesian optimal interval phase I dose escalation design was used to establish the maximum tolerated dose and recommended phase 2 dose (RP2D). Results. Nineteen patients with a range of solid tumors were enrolled. The most common treatment-related adverse events of any grade were diarrhea (42.1%, 8/19), followed by rash (36.8%, 7/19) and nausea (21.1%, 4/19). The combination RP2D for oral ixazomib was 4.0 mg on days 1, 8, and 15 of a 28-day cycle, with oral erlotinib 150 mg daily. While no patient achieved RECIST v1.1 objective responses, 3 patients with advanced sarcoma experienced durable RECIST v1.1 stable disease ≥ 6 months (8.4, 10.6, and 15.7 months) and the best response was -13% decrease in clear cell sarcoma. Conclusions. The combination of erlotinib and ixazomib was safe and well tolerated among patients with advanced cancer, with preliminary signals of antitumor activity in patients with advanced sarcoma.

Author response to Cunha et al

The need to identify biomarkers to predict immunotherapy response for rare cancers has been long overdue. We aimed to study this in our paper, 'Radiomics analysis for predicting pembrolizumab response in patients with advanced rare cancers'. In this response to the Letter to the Editor by Cunha et al, we explain and discuss the reasons behind choosing LASSO (Least Absolute Shrinkage and Selection Operator) and XGBoost (eXtreme Gradient Boosting) with LOOCV (Leave-One-Out Cross-Validation) as the feature selection and classifier method, respectively for our radiomics models. Also, we highlight what care was taken to avoid any overfitting on the models. Further, we checked for the multicollinearity of the features. Additionally, we performed 10-fold cross-validation instead of LOOCV to see the predictive performance of our radiomics models.

Abstract 974: Phase II trial of the Wee1 inhibitor adavosertib in advanced refractory solid tumors with CCNE1 amplification

Background: Wee1 kinase, which prevents premature mitotic entry by inhibiting cyclin-dependent kinases (CDKs), may be essential when cyclin E1 is overexpressed in order to prevent DNA damage and cell death. In preclinical studies, cancer models harboring CCNE1 amplification are highly sensitive to treatment with adavosertib, a Wee1 kinase inhibitor. A multicenter phase 2 study was conducted to assess the antitumor activity of adavosertib in patients with CCNE1 amplified advanced refractory solid tumors.

Methods: Patients with advanced refractory solid tumors harboring CCNE1 amplification pre-identified in a Clinical Laboratory Improvement Amendments (CLIA)-certified laboratory were eligible. They had refractory disease, on standard options available, or they declined standard-of-care therapy. Eligible patients must be aged ≥ 18 years and had measurable disease per RECIST (Response Evaluation Criteria in Solid Tumors) 1.1, ECOG (Eastern Cooperative Oncology Group) performance status of 0-1, and adequate organ functions. After informed consent, patients received adavosertib 300 mg daily on days 1 to 5 and 8 to 12 of a 21-day cycle. The primary endpoint was objective response rate (ORR). The trial employed Simon's two-stage design.

Results: Between January 22, 2019 and May 20, 2020, 29 patients with 12 tumor types were enrolled on study: ovarian = 14, breast = 3, endometrial = 2; and carcinosarcoma, cholangiocarcinoma, esophageal, gallbladder, germ cell tumor, melanoma, prostate, sarcoma, sarcomatoid and urothelial = 10 (1 each tumor). Median follow-up was 11.7 months. The median line of prior systemic therapy was 4 (range 1-8). Twenty-seven patients were evaluable for response. In these patients, 7 confirmed partial responses (PR) were observed, for an ORR of 25.9% (95% CI 15.1-47.5%). The median progression-free survival was 4.0 months and one-year overall survival was 55%. In 13 patients with measurable high-grade serous ovarian cancer, 5 achieved PR (38.5%) and 8 had stable disease ≥6 months/PR (61.5%). Other PRs were seen in 1 urothelial carcinoma and 1 melanoma. Fifteen patients experienced grade 3 or higher treatment-related adverse events: neutropenia (24%), thrombocytopenia (17%), anemia (14%), nausea (17%), diarrhea (17%) and fatigue (17%). Sixteen patients required dose duction of adavosertib to 250 mg, and 7 further to 200 mg. Biomarker analysis is ongoing to investigate potential biomarkers of response.

Conclusions: Adavosertib monotherapy demonstrates promising clinical activity in patients with refractory solid tumors harboring CCNE1 amplification, especially in high-grade serous ovarian cancer. Further exploration of adavosertib in CCNE1 amplified high grade serous ovarian cancer is warranted.

Citation Format: Siqing Fu, Shuyang Yao, Yuan Yuan, Rebecca A. Previs, Anthony D. Elias, Richard Carvajal, Thomas J. George, Ying Yuan, Yuko Yamamura, Shannon Westin, Yan Xing, Ecaterina E. Ileana Dumbrava, Daniel D. Karp, Sarina A. Piha-Paul, Apostolia M. Tsimberidou, Jordi Rodon, Naoko Takebe, Charles Kunos, Karen Lu, Khanda Keyomarsi, Funda Meric-Bernstam. Phase II trial of the Wee1 inhibitor adavosertib in advanced refractory solid tumors with CCNE1 amplification [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 974.

Phase 2 study of pembrolizumab in patients with advanced rare cancers

Background

Patients with advanced rare cancers have poor prognosis and few treatment options. As immunotherapy is effective across multiple cancer types, we aimed to assess pembrolizumab (programmed cell death 1 (PD-1) inhibitor) in patients with advanced rare cancers.

Methods

In this open-label, phase 2 trial, patients with advanced rare cancers whose tumors had progressed on standard therapies, if available, within the previous 6 months were enrolled in nine tumor-specific cohorts and a 10th cohort for other rare histologies. Pembrolizumab 200 mg was administered intravenously every 21 days. The primary endpoint was non-progression rate (NPR) at 27 weeks; secondary endpoints were safety and tolerability, objective response rate (ORR), and clinical benefit rate (CBR).

Results

A total of 127 patients treated between August 15, 2016 and July 27, 2018 were included in this analysis. At the time of data cut-off, the NPR at 27 weeks was 28% (95% CI, 19% to 37%). A confirmed objective response (OR) was seen in 15 of 110 (14%) evaluable patients (complete response in one and partial response in 14). CBR, defined as the percentage of patients with an OR or stable disease ≥4 months, was 38% (n=42). Treatment was ongoing in 11 of 15 patients with OR at last follow-up. In the cohort with squamous cell carcinoma (SCC) of the skin, the NPR at 27 weeks was 36%, ORR 31%, and CBR 38%. In patients with adrenocortical carcinoma (ACC), NPR at 27 weeks was 31%, ORR 15%, and CBR 54%. In the patients with carcinoma of unknown primary (CUP), NPR at 27 weeks was 33%, ORR 23%, and CBR 54%. In the paraganglioma–pheochromocytoma cohort, NPR at 27 weeks was 43%, ORR 0%, and CBR 75%. Treatment-related adverse events (TRAEs) occurred in 66 of 127 (52%) patients, and 12 (9%) had grade ≥3 TRAEs. The most common TRAEs were fatigue (n=25) and rash (n=17). There were six deaths, all of which were unrelated to the study drug.

Conclusions

The favorable toxicity profile and antitumor activity seen in patients with SCC of skin, ACC, CUP, and paraganglioma–pheochromocytoma supports further evaluation of pembrolizumab in this patient population.

Trial registration number

NCT02721732

First-in-human biomarker-driven phase I trial of the potent and selective glutaminase-1 (GLS1) inhibitor IACS-6274 (IPN60090) in patients (pts) with molecularly selected advanced solid tumors

3001

Background: Glutamine metabolism is frequently deregulated in different cancers, including tumors harboring KEAP1/ NFE2L2 mutations or those expressing low Asparagine Synthetase (ASNS) levels. IACS-6274 is a potent oral GLS1 inhibitor discovered at MD Anderson Cancer Center with excellent pharmacokinetics (PK) and antitumor activity in biomarker-defined preclinical models. Methods: Pts with advanced solid tumors received IACS-6274 BID at escalating doses using a phase 1 BOIN design. PK and pharmacodynamic (PD) studies were conducted in serial tumor and/or blood samples. Peripheral glutamine metabolism was assessed in peripheral blood mononuclear cells (PBMC) to assess glutamine metabolism via 13C-isotope labelling. Predictive biomarker studies included tumor analyses for KEAP1, NFE2L2, STK11, NF1 mutations and IHC for ASNS loss. Results: 22 pts with advanced ovarian (n=8), NSCLC (n=7), melanoma (n=2), leiomyosarcoma, gastric, anal, endometrial and HNSCC (all n=1) received IACS-6274 at 20 (n=1), 40 (n=1), 80 (n=1), 120 (n=4), 180 (n=11) or 240 (n=4) mg BID. Molecular alterations assessed included pts with ASNS loss (n=6), STK11 (n=5), KEAP1 (n=5), NFE2L2 (n=4) and NF1 (n=1). Prior lines of therapies: 2-4 (n=12); ≥5 (n=10). Common IACS-6274-related adverse events included G1-2 photopsia (n=7), photophobia (n=7), increased creatinine (n=4) and AST (n=4). Less common G3 toxicities at 180 and 240 mg included reversible nausea (n=3), vomiting and fatigue (n=2). Dose-limiting toxicities of G3 acute renal failure and PRES syndrome were seen in one patient at 240mg BID, which fully resolved. Plasma exposures showed a dose-dependent increase across doses with observed half-life ̃12 hrs. Patients at 180mg displayed steady-state exposures at C1D14 with Cmax of 45.8 μM +/- 18.6 μM and average AUC(0-12hrs) of 382.48 h*μM +/- 159.27 h*μM. Glutamate to glutamine ratios decreased in PBMC samples in pts at C1D14 vs baseline; pts at 120, 180 and 240 mg had inhibition of 82.5% (P<0.0001), 83.9% (P<0.0001) and 85.3% (P<0.0001), respectively, exceeding doses predicted to be efficacious in preclinical models. A robust PK/PD relationship was established across doses (P<0.0001). The recommended phase 2 dose was 180mg BID. Best RECISTv1.1 response was stable disease (SD) in 17 of 20 evaluable pts. Disease control rate at 12 weeks was 60%. Durable RECISTv1.1 SD ≥6 months +/- tumor regression were seen in pts with advanced ASNS-loss ovarian cancer (n=2), PD-1/L1-exposed melanoma (n=2) and NF1 mutant leiomyosarcoma (n=1). Conclusions: IACS-6274 was well tolerated at biologically active doses with good human PK, significant PD target modulation and preliminary antitumor activity observed. The clinical trial assessment of rational combinations to maximize benefit in molecularly-selected pts is initiating. Clinical trial information: NCT03894540.

A phase 1b study of novel immunogenic cell death inducer PT-112 plus PD-L1 inhibitor avelumab in metastatic castrate-resistant prostate cancer (mCRPC) patients

e17025

Background: PT-112 is a novel pyrophosphate-platinum conjugate that induces immunogenic cell death, reaches highest concentrations in bone (osteotropism), and synergizes with immune checkpoint inhibitors (ICIs) in preclinical models. Phase I studies in solid tumors, as monotherapy and in combination with PD-L1 inhibitor avelumab (“PAVE”), as well as in multiple myeloma as monotherapy have demonstrated that PT-112 is well-tolerated and active. We present updated safety and exploratory efficacy findings in a mCRPC sub-population treated with PAVE, including a cohort of patients at a lower-frequency dosing schedule. Methods: A total of 32 mCRPC patients (pts) received 800 mg of avelumab on days 1 and 15 of a 28-day cycle, of whom 18 received PT-112 on days 1, 8 and 15 at 200mg/m2 (n = 17) or 150 mg/m2 (n = 1); a separate cohort of 14 received PT-112 on days 1 and 15 at 300 mg/m2 (n = 13) or 200mg/m2 (n = 1). Results: Median age was 68 (range 47-87) and number of prior lines of therapy (Tx) was 7 (2-12), including prior platinum-containing therapy in 11 (34%) and ICI Tx in 9 pts (28%). Baseline grade 2 anemia was seen in 7 (22%) pts. The most common treatment-related adverse events (TRAEs) were anemia (47%) and thrombocytopenia (41%); 23 pts (72%) had ≥1 grade 3-4 TRAE, with no cases of bleeding, sepsis, or grade 5 TRAEs. Antitumor effects included 8 (25%) pts with a PSA reduction of ≥50% (PSA50); 5 (16%) were maintained through ≥1 follow-up. Of ten pts with RECIST-measurable disease, 3 had tumor volume reductions, one with a confirmed partial response (PR). Twenty-four (75%) pts experienced a reduction in serum alkaline phosphatase (ALP) (median reduction 15%), and improvement in patient-reported pain and quality of life was observed. For the 13 pts given 300 mg/m2 PT-112 bi-weekly, 7 (54%) had prior platinum-containing Tx and 4 (31%) had baseline grade 2 anemia. The most common TRAEs were anemia (69%) and thrombocytopenia (54%), with 11 (85%) pts having ≥1 grade 3-4 TRAE. Four pts (31%) had PSA50 reductions; 3 (23%) were maintained through ≥1 follow-up. Conclusions: PAVE is safe and generally well tolerated in mCRPC patients at the doses and schedules tested, providing meaningful antitumor effects in heavily pre-treated patients, including tumor volume, PSA and ALP reductions. Reductions in ALP may be indicative of anti-cancer activity at bone sites of disease. Although the sample sizes are small, the frequency of confirmed PSA50 responses and of grade 3-4 TRAEs was slightly higher in the group receiving biweekly 300 mg/m2 PT-112, and higher rates of TRAEs may be explained by higher baseline anemia and/or prior platinum Tx. Further clinical investigation of the combination of PT-112 plus ICIs in a less heavily pre-treated mCRPC population is warranted. A phase 2 study of PT-112 monotherapy in mCRPC is ongoing. Clinical trial information: NCT03409458.

Patients with advanced solid cancers treated with ERK inhibitors exhibit pseudo-progession in lymphatic nodes

3138

Background: ERK1/2 signaling is often overactivated in cancer, especially in patients with molecular alterations activating the MAPK pathway. MAPK pathway inhibition can result in the increase of CD8+ and CD4+ T-cells and decreased expression of immunosuppressive cytokines. Methods: This is a retrospective study of 52 patients with advanced solid cancers and oncogenic alterations in the MAPK pathway, who were treated in phase I/II clinical trials with five different single agent ERK1/2 inhibitors at MD Anderson Cancer Center. We reviewed serial PET and/or CT imaging obtained before therapy, on therapy, and after therapy completion. We evaluated dynamic changes in the lymphatic nodes (LN) in the context of overall response per RECIST 1.1 and other outcomes. Results: Of the 52 patients, 19 (37%) patients were evaluated with serial PET/CT and 33 (63%) with serial CT imaging only. Of the 19 patients evaluated with PET/CT, 12 (63%) demonstrated increased FDG uptake in LN compared to pre-treatment imaging (LN enlargement, n = 9; no LN enlargement, n = 3) discrepant from the known target and non-target lesions. These 12 patients were on therapy with ERK inhibitors (11 at doses > recommended phase 2 dose [RP2D]) for a median of 3.6 months (range, 1.8-12 months) with a best response per RECIST 1.1. as follows: partial response, n = 1; stable disease (SD), n = 10; progressive disease (PD), n = 1. Of interest, in 6 of those 12 patients, FDG uptake in LN decreased or resolved after treatment discontinuation. Further, one patient had a biopsy of an emerged LN, which showed lymphocytic infiltrate without tumor cells. Of the 33 patients evaluated with CT only, 5 (15%) demonstrated increased size of LN discrepant from the known target and non-target lesions compared to pre-treatment imaging. These 5 patients were on therapy with ERK inhibitors (all at doses < RP2D) for a median of 1.4 months (range, 1.1-3.5 months) with a best response per RECIST 1.1. as follows: SD, n = 2; PD, n = 3. Of interest, in 2 of those 5 patients, size of LN decreased or resolved after treatment discontinuation. In addition, one patient had a biopsy of an emerged LN, which showed lymphoid aggerates without tumor cells. Conclusions: Our data suggest that treatment with ERK inhibitors can result in activation of the lymphatic nodes, which can manifest as pseudo-progression. This can lead to an inconclusive assessment of their therapeutic benefit and further suggests exploration of the potential synergistic effects with immune therapy.

Initiative for Molecular Profiling and Advanced Cancer Therapy (IMPACT2): Challenges and Opportunities in Conducting an MD Anderson Randomized Study in Precision Oncology

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Background: Precision oncology is associated with favorable outcomes in selected patients with cancer. Our first IMPACT trial (IMPACT1) demonstrated that in sequential patients with advanced cancer who had tumor molecular testing and participated in phase I clinical trials, matched targeted therapy (MTT) was associated with superior rates of response, progression-free survival (PFS) and overall survival compared with those of patients who received non-MTT. Despite the statistical significance for these outcomes, the study was non-randomized. Recognizing that it would be difficult to randomize patients we nonetheless undertook IMPACT2, a phase 2 randomized study to determine whether patients treated on the basis of tumor genomic alterations have longer PFS compared to those whose treatment is not selected on the basis of molecular alteration analysis. Methods: Patients with metastatic cancer undergo a tumor biopsy and genomic profiling. Patients are presented at tumor board and are offered to be randomized between two arms: MTT or non-MTT, when criteria (biomarker present, available clinical trial, eligibility criteria met, insurance approval) are met. In April 2019, we amended the trial to include a “patient-preference” cohort for each arm. Patients who decline randomization are offered choice of arm (ClinicalTrials.gov: NCT02152254). The primary analysis will use both randomized and patient-preference cohorts based on a Bayesian hierarchical model that “borrows” from the patient-preference cohorts to the extent to which its PFS agrees with that in the randomization cohort. Results: The key barriers randomizing patients with actionable molecular alterations are patient-related (advanced, metastatic setting requiring immediate intervening therapy; decline in performance status, organ function; or death); drug-related (FDA-approved drug available; or unavailable MTT against key driver biomarker) or financial (no insurance coverage of MTT; lack of patient resources to participate in trials). As the study spans over a few years, some investigational agents that were considered non-MTT at the time of treatment assignment were later proven to be MTT (e.g., immunotherapeutic agents targeting high tumor mutational burden); and/or were approved by the FDA. Conclusions: Although randomized trials have been considered the gold standard in drug development, such studies in the advanced metastatic setting are complicated. The benefit of Precision Oncology has been exemplified in individual patients who were treated with biomarker-selected therapy. The adaptive design of IMPACT2 enables patient randomization despite the evolving tumor biomarkers and the plethora of investigational drugs. IMPACT2 provides insights for the development of cancer genome-based medicine. Outcomesfor randomized patients are awaited. Clinical trial information: NCT02152254.

Phase I study of TT-00420, a multiple kinase inhibitor, as a single agent in advanced solid tumors

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Background: TT-00420 is a spectrum-selective multi-kinase inhibitor that targets cell proliferation, angiogenesis, and immune-oncology pathways by inhibiting Aurora kinases A/B and Janus kinases (JAK) involved in cytokine signaling and receptor tyrosine kinases (FGFRs and VEGFRs) involved in the tumor microenvironment. TT-00420 has demonstrated anti-tumor activity in both in vitro and in vivo preclinical models of solid tumors, including triple-negative breast cancer (TNBC) and cholangiocarcinoma (CCA). Methods: The phase I, first-in-human dose escalation and expansion study of TT-00420 is enrolling adult patients with advanced or metastatic solid tumors. TT-00420 capsules in 1 mg or 5 mg formulation are administered orally once daily in 28-day cycles. Dose escalation is guided by Bayesian modeling with overdose control. The primary safety endpoints are to determine dose limiting toxicities (DLTs) and a dose recommended for dose expansion (DRDE). Secondary endpoints include pharmacokinetics (PK) and preliminary efficacy evaluated per RECIST v1.1 criteria. Results: As of February 17, 2021, 40 advanced solid tumor patients were enrolled in dose escalation cohorts and received at least one dose of TT-00420 in 7 dose levels: 1 mg q.d. (N=1), 3 mg q.d. (N=1), 5 mg q.d. (N=4), 8 mg q.d. (N=10), 10 mg q.d. (N=6), 12 mg q.d. (N=12), and 15 mg q.d. (N=6). DLTs were observed in 3 out of 32 DLT-evaluable patients, including 1 patient at 8 mg q.d. who had grade (Gr) 3 palmar-plantar erythrodysaesthesia syndrome and 2 patients at 15 mg q.d. who both had Gr 3 hypertension. Suspected adverse events (AEs) reported in ≥ 20% of patients across all tested dose levels include hypertension (any grade: n=17, 42.5%; Gr 3: n=8, 20.0%), diarrhea (n=10, 25.0%; Gr 3: n=1, 2.5%), vomiting (n=9, 22.5%; Gr 3: n=0), palmar-plantar erythrodysaesthesia syndrome (n=9, 22.5%; Gr 3: n=1, 2.5%), and nausea (n=8, 20.0%; Gr 3: n=1, 2.5%). No Gr 4 AEs, regardless of causality, were reported. Out of 26 patients who had at least one post-baseline scan, 4 (15.4%) had a best overall objective response of partial response (PR) and 13 (50.0%) had stable disease (SD). Of the patients who achieved PRs are 2 CCA patients (8 mg q.d., n=1; 10 mg q.d., n=1), 1 HER2-negative breast cancer patient (12 mg q.d.), and 1 TNBC (10 mg q.d.). Both CCA patients with PRs had disease control for ≥ 8 months. Of the patients who achieved SD, 1 salivary gland patient (5 mg q.d.) and 1 CCA patient (10 mg q.d.) had disease control for 8 months, and 2 TNBC patients (5 mg q.d., n=1; 8 mg q.d., n=1) had disease control for 6 months prior to disease progression. Conclusions: Toxicities observed in dose escalation cohorts were manageable with concomitant treatment and/or dose interruptions of TT-00420. 12 mg p.o. q.d. was recommended as the dose for dose expansion cohort for further safety and efficacy evaluation of TT-00420 capsules with focus on enrollment of TNBC and CCA patients. Clinical trial information: NCT03654547.

A Phase I Trial of the MET/ALK/ROS1 Inhibitor Crizotinib Combined with the VEGF Inhibitor Pazopanib in Patients with Advanced Solid Malignancies

BACKGROUND

Crizotinib inhibits ALK, MET and ROS1 tyrosine kinases but the development of resistance to monotherapy is an issue. The anti-angiogenic properties of pazopanib could overcome crizotinib drug resistance. Additionally, the anti-angiogenic properties of crizotinib could augment the clinical efficacy of pazopanib.

METHODS

We evaluated the safety and responses in patients with advanced solid tumors treated with crizotinib and pazopanib.

RESULTS

Eighty-two patients (median age 53 years, range 18-78 years) were enrolled. The median number of prior systemic therapies was 3 (range, 0-8). We were able to dose escalate to dose level 8 (crizotinib 250 mg twice daily and pazopanib 800 mg daily) with no MTD identified. Grade 3 or 4 toxicities were seen in 32% of patients with the highest prevalence being fatigue (n=9, 11%), diarrhea (n=6, 7%), vomiting (n=3, 4%), anemia (n=2, 2%) and ALT increased (n=2, 2%). Of the 82 patients, 61 (74%) had measurable disease by RECISTv1.1 and reached first restaging (6 weeks). Partial response (PR) was observed in 6/61 (10%) patients, and stable disease (SD) lasting ≥6 months was observed in 10/61 patients (16%) (total = 16/61 (26%) of patients with SD ≥6 months/PR).

CONCLUSION

Dose level 6 (crizotinib 200 mg twice daily and pazopanib 600 mg daily) was the most tolerable dosing of the combination and can be used in future studies. We also observed moderate clinical activity in patients with advanced solid tumors that had received numerous prior therapies.

Implementation of a Novel Web-Based Lesion Selection Tool to Improve Acquisition of Tumor Biopsy Specimens

Introduction

For maximum utility of molecular characterization by next-generation sequencing (NGS) and better understanding of tumor microenvironment with immune correlates analysis, biopsy specimens must yield adequate tumor tissue, and sequential biopsy specimens should sample a consistent site. We developed a web-based lesion selection tool (LST) that enables management and tracking of the biopsy specimen collections.

Methods

Of 145 patients, the LST was used for 88 patients; the other 57 served as controls. We evaluated consistency of the lesion biopsied in longitudinal collections, number of cores obtained, and cores with adequate tumor cellularity for NGS. The Fisher exact test and Wilcoxon rank sum test were used to identify differences between the groups.

Results

The analysis included 30 of 88 (34%) patients in the LST group and 52 of 57 (91%) in the control group. The LST workflow ensured 100% consistency in the lesions biopsied compared with 75% in the control group in longitudinal collections and increased the proportion of patients in whom at least five cores were collected per biopsy.

Conclusions

The novel LST platform facilitates coordination, performance, and management of longitudinal biopsy specimens. Use of the LST enables sampling of the designated lesion consistently, which is likely to accurately inform us the effect of the treatment on tumor microenvironment and evolution of resistant pathways. Such studies are important translational component of any clinical trials and research as they guide the development of next line of therapy, which has significant effect on clinical utility. However, validation of this approach in a larger study is warranted.

Patient-Reported Out-of-Pocket Costs and Financial Toxicity During Early-Phase Oncology Clinical Trials

BACKGROUND

Clinical trials are an important therapeutic option for patients with cancer. Although financial burden in cancer treatment is well documented, the financial burden associated with clinical trials is not well understood.

PATIENTS AND METHODS

We conducted a survey regarding economic burden and financial toxicity in patients with cancer enrolled in phase I clinical trials for >1 month. Financial toxicity score was assessed using the Comprehensive Score for Financial Toxicity survey. Patients also reported monthly out-of-pocket (OOP) costs.

RESULTS

Two hundred and thirteen patients completed the survey (72% non-Hispanic White; 45% with annual income ≤$60,000; 50% lived >300 miles from the clinic; 37% required air travel). Forty-eight percent of patients had monthly OOP costs of at least $1,000. Fifty-five percent and 64% of patients reported unanticipated medical and nonmedical expenses, respectively. Worse financial toxicity was associated with yearly household income <$60,000 (odds ratio [OR]: 2.7; p = .008), having unanticipated medical costs (OR: 3.2; p = .024), and living >100 miles away from the clinical trial hospital (OR: 2.3; p = .043). Non-White or Hispanic patients (OR: 2.5; p = .011) and patients who were unemployed or not working outside the home (OR: 2.5; p = .016) were more likely to report high unanticipated medical costs.

CONCLUSION

Among patients with cancer participating in clinical trials, economic burden is high, and most of patients' OOP costs were nonmedical costs. Financial toxicity is disproportionally higher in patients with lower income and those who travel farther, and unexpected medical costs were more common among non-White or Hispanic patients. OOP costs can be substantial and are often unexpected for patients.

IMPLICATIONS FOR PRACTICE

The financial burden of cancer treatment is well documented, but there are limited data regarding the financial burden associated with cancer clinical trials. This study surveyed 213 patients enrolled in early-phase clinical trials. Monthly out-of-pocket costs were at least $1000 for nearly half of patients. Worse financial toxicity was associated with income <$60,000 and living farther away from the hospital. Racial/ethnic minorities had higher rates of unanticipated medical costs. These data help to quantify the high financial burden for patients and may reveal a cause of disparities in clinical trial enrollment for underrepresented populations.

Overview of Ocular Side Effects of Selinexor

BACKGROUND

The aim of this review is to elucidate the type and frequency of ocular adverse events associated with selinexor with a goal to quantify the occurrence of these events in our investigator-initiated trial.

METHODS

We retrospectively reviewed medical records of 174 patients treated with at least one dose of selinexor in combination with multiple standard chemotherapy or immunotherapy agents between July 2015 and July 2020 at a comprehensive cancer center in the U.S. All reported ocular adverse events were assessed.

RESULTS

A total of 174 patient medical records were reviewed. All patients received at least one dose of selinexor in combination with multiple standard chemotherapy or immunotherapy agents in our cohort of patients with advanced malignancies. A total of 34 (19.54%) patients experienced 37 ocular adverse events. The most frequently reported ocular symptom was blurred vision, which was reported in 22 (12.64%) patients. The most frequently reported treatment-related adverse event was dry eye syndrome reported in 21 (12.1%) patients, and 19 (10.9%) of them were diagnosed with mild dry eye. The second most common treatment-related adverse event was the progression of age-related nuclear sclerosis (cataract) reported in 7 (4.0%) patients. None of the ocular adverse events required therapy discontinuation.

CONCLUSION

Our findings highlight that ocular adverse events associated with oral selinexor were mild. The most frequently reported ocular treatment-related adverse events were mild dry eye and progression of age-related nuclear sclerosis. None of the ocular adverse events required therapy discontinuation.

IMPLICATIONS FOR PRACTICE

Patients receiving selinexor in combination with multiple standard chemotherapy or immunotherapy agents were reviewed, with a total of 34 patients experiencing 37 ocular adverse events. Findings highlight that ocular adverse events associated with oral selinexor were mild. The most frequently reported ocular treatment-related adverse events were mild dry eye and progression of age-related nuclear sclerosis. None of the ocular adverse events required therapy discontinuation.

Radiomics analysis for predicting pembrolizumab response in patients with advanced rare cancers

BACKGROUND

We present a radiomics-based model for predicting response to pembrolizumab in patients with advanced rare cancers.

METHODS

The study included 57 patients with advanced rare cancers who were enrolled in our phase II clinical trial of pembrolizumab. Tumor response was evaluated using Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 and immune-related RECIST (irRECIST). Patients were categorized as 20 "controlled disease" (stable disease, partial response, or complete response) or 37 progressive disease). We used 3D-slicer to segment target lesions on standard-of-care, pretreatment contrast enhanced CT scans. We extracted 610 features (10 histogram-based features and 600 second-order texture features) from each volume of interest. Least absolute shrinkage and selection operator logistic regression was used to detect the most discriminatory features. Selected features were used to create a classification model, using XGBoost, for the prediction of tumor response to pembrolizumab. Leave-one-out cross-validation was performed to assess model performance.

FINDINGS

The 10 most relevant radiomics features were selected; XGBoost-based classification successfully differentiated between controlled disease (complete response, partial response, stable disease) and progressive disease with high accuracy, sensitivity, and specificity in patients assessed by RECIST (94.7%, 97.3%, and 90%, respectively; p<0.001) and in patients assessed by irRECIST (94.7%, 93.9%, and 95.8%, respectively; p<0.001). Additionally, the common features of the RECIST and irRECIST groups also highly predicted pembrolizumab response with accuracy, sensitivity, specificity, and p value of 94.7%, 97%, 90%, p<0.001% and 96%, 96%, 95%, p<0.001, respectively.

CONCLUSION

Our radiomics-based signature identified imaging differences that predicted pembrolizumab response in patients with advanced rare cancer.

INTERPRETATION

Our radiomics-based signature identified imaging differences that predicted pembrolizumab response in patients with advanced rare cancer.

Phase I Study of Everolimus, Letrozole, and Trastuzumab in Patients with Hormone Receptor-positive Metastatic Breast Cancer or Other Solid Tumors

PURPOSE

Doublets of everolimus with letrozole or trastuzumab have demonstrated activity against HER2-positive breast cancer, suggesting that the triple combination can have synergistic anticancer activity.

PATIENTS AND METHODS

This first-in-human dose-escalation study (NCT02152943) enrolled patients with hormone receptor- positive, HER2-positive (defined by amplification, overexpression, or mutation) treatment-refractory advanced cancers to receive escalating doses (3+3 design) of daily oral letrozole (days 1-21), daily oral everolimus (days 1-21), and intravenous trastuzumab (day 1) every 21 days to determine dose-limiting toxicities (DLT) and MTD or recommended phase II dose (RP2D).

RESULTS

A total of 32 patients with hormone receptor-positive, HER2-positive (amplification, n = 27; overexpression, n = 1; and mutation, n = 4) advanced breast cancer (n = 26) or other cancers (n = 6) were enrolled. The most frequent grade ≥3 adverse events included hyperglycemia (n = 4), anemia (n = 3), thrombocytopenia (n = 2), and mucositis (n = 2). DLTs included grade 3 mucositis and grade 4 neutropenia, and trastuzumab given as an 8 mg/kg loading dose on day 1 of cycle 1 followed by a 6 mg/kg maintenance dose on day 1 of subsequent cycles plus 10 mg everolimus daily and 2.5 mg letrozole daily every 21 days was declared as RP2D. Five patients with breast cancer (four with HER2 amplification and one with HER2 mutation) had partial responses. HER2 amplification in circulating cell-free DNA at baseline was associated with shorter progression-free and overall survival durations (P < 0.05).

CONCLUSIONS

Everolimus, letrozole, and trastuzumab have a favorable safety profile and elicit encouraging signals of anticancer activity in patients with heavily pretreated hormone receptor- and HER2-positive advanced cancers.