Safety and efficacy of pralsetinib in RET fusion-positive non-small-cell lung cancer including as first-line therapy: update from the ARROW trial.

BACKGROUND: RET fusions are present in 1%-2% of non-small-cell lung cancer (NSCLC). Pralsetinib, a highly potent, oral, central nervous system-penetrant, selective RET inhibitor, previously demonstrated clinical activity in patients with RET fusion-positive NSCLC in the phase I/II ARROW study, including among treatment-naive patients. We report an updated analysis from the ARROW study. PATIENTS AND METHODS: ARROW is a multi-cohort, open-label, phase I/II study. Eligible patients were ≥18 years of age with locally advanced or metastatic solid tumours and an Eastern Cooperative Oncology Group performance status of 0-2 (later 0-1). Patients initiated pralsetinib at the recommended phase II dose of 400 mg once daily until disease progression, intolerance, consent withdrawal, or investigator's decision. The co-primary endpoints (phase II) were overall response rate (ORR) by blinded independent central review and safety. RESULTS: Between 17 March 2017 and 6 November 2020 (data cut-off), 281 patients with RET fusion-positive NSCLC were enrolled. The ORR was 72% [54/75; 95% confidence interval (CI) 60% to 82%] for treatment-naive patients and 59% (80/136; 95% CI 50% to 67%) for patients with prior platinum-based chemotherapy (enrolment cut-off for efficacy analysis: 22 May 2020); median duration of response was not reached for treatment-naive patients and 22.3 months for prior platinum-based chemotherapy patients. Tumour shrinkage was observed in all treatment-naive patients and in 97% of patients with prior platinum-based chemotherapy; median progression-free survival was 13.0 and 16.5 months, respectively. In patients with measurable intracranial metastases, the intracranial response rate was 70% (7/10; 95% CI 35% to 93%); all had received prior systemic treatment. In treatment-naive patients with RET fusion-positive NSCLC who initiated pralsetinib by the data cut-off (n = 116), the most common grade 3-4 treatment-related adverse events (TRAEs) were neutropenia (18%), hypertension (10%), increased blood creatine phosphokinase (9%), and lymphopenia (9%). Overall, 7% (20/281) discontinued due to TRAEs. CONCLUSIONS: Pralsetinib treatment produced robust efficacy and was generally well tolerated in treatment-naive patients with advanced RET fusion-positive NSCLC. Results from the confirmatory phase III AcceleRET Lung study (NCT04222972) of pralsetinib versus standard of care in the first-line setting are pending.

Association of clinical factors and recent anticancer therapy with COVID-19 severity among patients with cancer: a report from the COVID-19 and Cancer Consortium.

BACKGROUND: Patients with cancer may be at high risk of adverse outcomes from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We analyzed a cohort of patients with cancer and coronavirus 2019 (COVID-19) reported to the COVID-19 and Cancer Consortium (CCC19) to identify prognostic clinical factors, including laboratory measurements and anticancer therapies. PATIENTS AND METHODS: Patients with active or historical cancer and a laboratory-confirmed SARS-CoV-2 diagnosis recorded between 17 March and 18 November 2020 were included. The primary outcome was COVID-19 severity measured on an ordinal scale (uncomplicated, hospitalized, admitted to intensive care unit, mechanically ventilated, died within 30 days). Multivariable regression models included demographics, cancer status, anticancer therapy and timing, COVID-19-directed therapies, and laboratory measurements (among hospitalized patients). RESULTS: A total of 4966 patients were included (median age 66 years, 51% female, 50% non-Hispanic white); 2872 (58%) were hospitalized and 695 (14%) died; 61% had cancer that was present, diagnosed, or treated within the year prior to COVID-19 diagnosis. Older age, male sex, obesity, cardiovascular and pulmonary comorbidities, renal disease, diabetes mellitus, non-Hispanic black race, Hispanic ethnicity, worse Eastern Cooperative Oncology Group performance status, recent cytotoxic chemotherapy, and hematologic malignancy were associated with higher COVID-19 severity. Among hospitalized patients, low or high absolute lymphocyte count; high absolute neutrophil count; low platelet count; abnormal creatinine; troponin; lactate dehydrogenase; and C-reactive protein were associated with higher COVID-19 severity. Patients diagnosed early in the COVID-19 pandemic (January-April 2020) had worse outcomes than those diagnosed later. Specific anticancer therapies (e.g. R-CHOP, platinum combined with etoposide, and DNA methyltransferase inhibitors) were associated with high 30-day all-cause mortality. CONCLUSIONS: Clinical factors (e.g. older age, hematological malignancy, recent chemotherapy) and laboratory measurements were associated with poor outcomes among patients with cancer and COVID-19. Although further studies are needed, caution may be required in utilizing particular anticancer therapies. CLINICAL TRIAL IDENTIFIER: NCT04354701.

Targeted therapy for advanced salivary gland carcinoma based on molecular profiling: results from MyPathway, a phase IIa multiple basket study.

BACKGROUND: Systemic therapy options for salivary cancers are limited. MyPathway (NCT02091141), a phase IIa study, evaluates targeted therapies in non-indicated tumor types with actionable molecular alterations. Here, we present the efficacy and safety results for a subgroup of MyPathway patients with advanced salivary gland cancer (SGC) matched to targeted therapies based on tumor molecular characteristics. PATIENTS AND METHODS: MyPathway is an ongoing, multiple basket, open-label, non-randomized, multi-center study. Patients with advanced SGC received pertuzumab + trastuzumab (HER2 alteration), vismodegib (PTCH-1/SMO mutation), vemurafenib (BRAF V600 mutation), or atezolizumab [high tumor mutational burden (TMB)]. The primary endpoint is the objective response rate (ORR). RESULTS: As of January 15, 2018, 19 patients with SGC were enrolled and treated in MyPathway (15 with HER2 amplification and/or overexpression and one each with a HER2 mutation without amplification or overexpression, PTCH-1 mutation, BRAF mutation, and high TMB). In the 15 patients with HER2 amplification/overexpression (with or without mutations) who were treated with pertuzumab + trastuzumab, 9 had an objective response (1 complete response, 8 partial responses) for an ORR of 60% (9.2 months median response duration). The clinical benefit rate (defined by patients with objective responses or stable disease >4 months) was 67% (10/15), median progression-free survival (PFS) was 8.6 months, and median overall survival was 20.4 months. Stable disease was observed in the patient with a HER2 mutation (pertuzumab + trastuzumab, n = 1/1, PFS 11.0 months), and partial responses in patients with the PTCH-1 mutation (vismodegib, n = 1/1, PFS 14.3 months), BRAF mutation (vemurafenib, n = 1/1, PFS 18.5 months), and high TMB (atezolizumab, n = 1/1, PFS 5.5+ months). No unexpected toxicity occurred. CONCLUSIONS: Overall, 12 of 19 patients (63%) with advanced SGC, treated with chemotherapy-free regimens matched to specific molecular alterations, experienced an objective response. Data from MyPathway suggest that matched targeted therapy for SGC has promising efficacy, supporting molecular profiling in treatment determination.

Comprehensive genomic profiles of metastatic and relapsed salivary gland carcinomas are associated with tumor type and reveal new routes to targeted therapies.

BACKGROUND: Relapsed/metastatic salivary gland carcinomas (SGCs) have a wide diversity of histologic subtypes associated with variable clinical aggressiveness and response to local and systemic therapies. We queried whether comprehensive genomic profiling could define the tumor subtypes and uncover clinically relevant genomic alterations, revealing new routes to targeted therapies for patients with relapsed and metastatic disease. PATIENTS AND METHODS: From a series of 85 686 clinical cases, DNA was extracted from 40 µm of formalin-fixed paraffin embedded (FFPE) sections for 623 consecutive SGC. CGP was carried out on hybridization-captured, adaptor ligation-based libraries (mean coverage depth, >500×) for up to 315 cancer-related genes. Tumor mutational burden was determined on 1.1 Mb of sequenced DNA. All classes of alterations, base substitutions, short insertions/deletions, copy number changes, and rearrangements/fusions were determined simultaneously. RESULTS: The clinically more indolent SGC including adenoid cystic carcinoma, acinic cell carcinoma, polymorphous low-grade adenocarcinoma, mammary analog secretory carcinoma, and epithelial-myoepithelial carcinomas have significantly fewer genomic alterations, TP53 mutations, and lower tumor mutational burden than the typically more aggressive SGCs including mucoepidermoid carcinoma, salivary duct carcinoma, adenocarcinoma, not otherwise specified, carcinoma NOS, and carcinoma ex pleomorphic adenoma. The more aggressive SGCs are commonly driven by ERBB2 PI3K pathway genomic alterations. Additional targetable GAs are frequently seen. CONCLUSIONS: Genomic profiling of SGCs demonstrates important differences between traditionally indolent and aggressive cancers. These differences may provide therapeutic options in the future.

Comprehensive genomic profiling of salivary mucoepidermoid carcinomas reveals frequent BAP1, PIK3CA, and other actionable genomic alterations.

Background: We sought to identify genomic alterations (GAs) in salivary mucoepidermoid carcinomas. Patients and methods: DNA was extracted from 48 mucoepidermoid carcinomas. Comprehensive genomic profiling (CGP) including the calculation to tumor mutational burden (TMB) was performed on hybridization-captured adaptor ligation-based libraries of 315 cancer-related genes plus introns from 28 genes frequently rearranged for cancer and evaluated for all classes of GAs. Results: A total of 183 GAs were found in 80 unique genes. High-grade tumors had more GAs (mean 5 ± 3.8) compared with low (2.3 ± 1.4) or intermediate (2.6 ± 1.5) (P = 0.019). TP53 GAs were seen in all tumor grades (41.7%) but were most common in high-grade malignancies (56%) (P = 0.047). CDKN2A GAs were seen in 41.6% of tumors. PI3K/mTOR pathway activation, including PI3KCA mutations, were more common in high grade (52%) than in low- and intermediate-grade tumors (4.3%) (P = 0.007). BAP1 GAs were observed in 20.8% of tumors and BRCA1/2 GAs present in 10.5% of specimens. ERBB2 amplifications were seen in only 8.3% of tumors. The TMB for this patient group was relatively low with only 5 (10%) of cases having greater than 10 mutations/megabase of sequenced DNA. Conclusion: CGP of salivary mucoepidermoid carcinomas revealed diverse GAs that may lead to customized treatment options for patients with these rare tumors.

A multicenter phase 1 study of PX-866 in combination with docetaxel in patients with advanced solid tumours.

BACKGROUND: This phase I, dose-finding study determined the safety, maximum tolerated dose (MTD)/recommended phase 2 dose (RP2D), pharmacokinetics, and antitumour activity of PX-866, a phosphatidylinositol 3-kinase inhibitor, combined with docetaxel in patients with incurable solid tumours. METHODS: PX-866 was administered at escalating doses (4-8 mg daily) with docetaxel 75 mg m⁻² intravenously every 21 days. Archived tumour tissue was assessed for potential predictive biomarkers. RESULTS: Forty-three patients were enrolled. Most adverse events (AEs) were grade 1 or 2. The most frequent study drug-related AE was diarrhoea (76.7%), with gastrointestinal disorders occurring in 79.1% (docetaxel-related) and 83.7% (PX-866-related). No dose-limiting toxicities were observed. The RP2D was 8 mg, the same as the single-agent MTD. Co-administration of PX-866 and docetaxel did not affect either drug's PKs. Best responses in 35 evaluable patients were: 2 partial responses (6%), 22 stable disease (63%), and 11 disease progression (31%). Eleven patients remained on study for >180 days, including 8 who maintained disease control on single-agent PX-866. Overall median progression-free survival (PFS) was 73.5 days (range: 1-569). A non-significant association between longer PFS for PIK3CA-MUT/KRAS-WT vs PIK3CA-WT/KRAS-WT was observed. CONCLUSION: Treatment with PX-866 and docetaxel was well tolerated, without evidence of overlapping/cumulative toxicity. Further investigation with this combination is justified.

Targeted therapies for ROS1-rearranged non-small cell lung cancer.

ROS1 gene fusions account for approximately 1-2% of all cases of non-small cell lung cancer (NSCLC). Similarly to anaplastic lymphoma kinase (ALK)-positive NSCLC, patients with ROS1+ NSCLC tend to have minimal smoking and be of the female sex. In most cases, adenocarcinoma is the dominant histology. The ROS1 gene has homology to ALK and this structural similarity formed the basis for utilizing ALK inhibitors for ROS1+ NSCLC. On the basis of impressive progression-free survival of 19.2 months from the PROFILE 1001 trial, crizotinib obtained Food and Drug Administration (FDA) approval as first-line therapy for treatment of ROS1+ NSCLC. Since then, there has been a growing appreciation of the incidence of brain metastases in ROS1+ NSCLC and rates of central nervous system progression on crizotinib. Additionally, appreciation of novel resistance mechanisms to crizotinib has led to the development of newer tyrosine kinase inhibitors (TKIs). In this review, we highlight known and emerging TKIs for the management of ROS1+ NSCLC.

Update on multikinase inhibitor therapy for differentiated thyroid cancer.

Curative therapies for radioiodine-refractory differentiated thyroid cancer remain lacking. However, oral multikinase inhibitors often allow for disease control and improved progression-free survival. Two agents, lenvatinib and sorafenib, have been approved for radioiodine-refractory differentiated thyroid cancer on the basis of phase III clinical trials showing marked response rates and improved progression-free survival over placebo. Several other multikinase inhibitors, including apatinib, axitinib, cabozantinib, pazopanib, sunitinib and vandetanib, have also been studied in phase II clinical trials, with varying response rates and comparable progression-free survival. Selective kinase inhibitors, including dabrafenib, vemurafenib, selumetinib and gefitinib, offer a more targeted approach and have also been studied in phase II clinical trials. While the emergence of these treatments has changed the landscape of management of advanced thyroid cancer, clinical challenges remain, and there are many areas of ongoing research.

New therapies for anaplastic thyroid cancer.

Anaplastic thyroid cancer is a rare but extremely aggressive type of thyroid cancer. Treatment typically consists of surgery, external beam radiotherapy and cytotoxic chemotherapy. However, available literature suggests only modest survival benefit for cytotoxic chemotherapy. Recent advances have suggested the combination of BRAF and MEK inhibition may have a profound and durable effect on patients with BRAFV600E-mutated anaplastic thyroid cancer, with a response rate of 69%. Other systemic treatments, including immunotherapies, have also shown promising but more limited results. Many clinical trials assessing the efficacy of kinase inhibitors and immunotherapies are currently ongoing.

Cabozantinib use in renal cell carcinoma.

In the last several years, many new drugs have been approved to treat metastatic renal cell carcinoma (RCC). Cabozantinib is a novel multikinase inhibitor with activity against vascular endothelial growth factor receptor (VEGFR), proto-oncogene tyrosine-protein kinase receptor Ret and other kinases that recently joined this impressive list of approved agents. Cabozantinib is an active agent in the preclinical and clinical setting, having recently demonstrated superiority over everolimus in a blinded, randomized phase III study of patients with progressive RCC after at least one prior line of antiangiogenic therapy. This agent's toxicity profile is similar to those of other multikinase inhibitors approved to treat RCC. This review will explore cabozantinib's pharmacologic and safety profile and its preclinical and clinical activity in RCC.

XactMice: humanizing mouse bone marrow enables microenvironment reconstitution in a patient-derived xenograft model of head and neck cancer.

The limitations of cancer cell lines have led to the development of direct patient-derived xenograft models. However, the interplay between the implanted human cancer cells and recruited mouse stromal and immune cells alters the tumor microenvironment and limits the value of these models. To overcome these constraints, we have developed a technique to expand human hematopoietic stem and progenitor cells (HSPCs) and use them to reconstitute the radiation-depleted bone marrow of a NOD/SCID/IL2rg(-/-) (NSG) mouse on which a patient's tumor is then transplanted (XactMice). The human HSPCs produce immune cells that home into the tumor and help replicate its natural microenvironment. Despite previous passage on nude mice, the expression of epithelial, stromal and immune genes in XactMice tumors aligns more closely to that of the patient tumor than to those grown in non-humanized mice-an effect partially facilitated by human cytokines expressed by both the HSPC progeny and the tumor cells. The human immune and stromal cells produced in the XactMice can help recapitulate the microenvironment of an implanted xenograft, reverse the initial genetic drift seen after passage on non-humanized mice and provide a more accurate tumor model to guide patient treatment.

Afatinib for the treatment of patients with EGFR-positive non-small cell lung cancer.

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are valuable treatments for EGFR-mutated non-small cell lung cancer (NSCLC). Anti-EGFR antibodies are widely used in the treatment of head and neck squamous cell carcinomas (HNSCC) and in KRAS wild-type colorectal cancer. The first-generation, reversible EGFR inhibitors erlotinib and gefitinib in the first-line setting provide superior progression-free survival and quality of life compared to conventional chemotherapy in NSCLC harboring activating EGFR mutations. However, these therapies eventually fail and new options are needed. Afatinib is a novel irreversible inhibitor of the ErbB family members EGFR, tyrosine kinase-type cell surface receptors HER2 and HER4. It shows preclinical efficacy in NSCLC with common EGFR-activating mutations and the T790M mutation typically associated with EGFR TKI resistance. Preclinical activity is seen in other tumor types as well, including HNSCC. Clinically, afatinib has been evaluated in the broad-reaching LUX Lung trial program, with significant activity seen in the first and later-line settings. It is also under investigation in multiple other tumor types. This review will stress on afatinib's preclinical pharmacology, pharmacokinetics and clinical activity with a focus on NSCLC.

Tivozanib: practical implications for renal cell carcinoma and other solid tumors.

Tivozanib is a recently developed, small-molecule tyrosine kinase inhibitor with specific affinity for the vascular endothelial growth factor receptor (VEGFR) family of kinases. Given known relevance of VHL (Von Hippel-Lindau disease tumor suppressor) deregulation in the clear cell variant of renal cell carcinoma, renal cell carcinoma remains an area of interest and subject of recent registration trials with this approach. TIVO-1, a phase III study evaluating tivozanib versus sorafenib in the first-line setting, met its primary endpoint of progression-free survival (11.9 months for tivozanib vs. 9.1 months for sorafenib), with a manageable toxicity profile, leading to formal consideration of regulatory approval in this setting. This review focuses on the preclinical development, pharmacokinetics and early clinical activity of tivozanib in renal cell carcinoma and other solid tumors.

New and established tyrosine kinase inhibitors for chronic myeloid leukemia.

Chronic myeloid leukemia (CML) is an uncommon malignancy, the treatment and prognosis of which have dramatically shifted over the last decade. Characterized by a translocation between chromosomes 9 and 22, known as the Philadelphia chromosome, small-molecule tyrosine kinase inhibitors (TKIs) targeted against the oncogenic BCR-ABL fusion protein have changed this once fatal disease into the model of targeted therapy. This article will review the pharmacological and clinical data supporting the use of imatinib and the second-generation TKIs dasatinib and nilotinib, and the novel TKIs bosutinib and ponatinib.

Axitinib, a new therapeutic option in renal cell carcinoma.

Axitinib is a small-molecule protein-tyrosine kinase receptor inhibitor specifically targeting this family of receptors, in addition to platelet-derived growth factor receptor and proto-oncogene c-Kit. Improved knowledge of kidney cancer development, and specifically mutations in the VHL gene, has supported the targeting of angiogenesis pathways. Axitinib is the most recently approved agent for use in metastatic renal cell carcinoma. This review will focus on the preclinical pharmacology, pharmacokinetics and clinical activity of this agent, and describe its place in the current treatment of renal cell carcinoma.

Vismodegib in basal cell carcinoma.

Vismodegib is a novel, small-molecule inhibitor of smoothened, a key component of the hedgehog signaling pathway. Increased hedgehog pathway signaling is critical in the development of hereditary and spontaneous basal cell carcinomas of the skin, and has been implicated in the development of a number of other tumors. In preclinical models, vismodegib demonstrated potent antitumor activity in hedgehog-dependent tumors, particularly basal cell carcinomas. Clinically, phase I and II studies showed dramatic anticancer activity in patients with advanced basal cell carcinomas. In January 2012, vismodegib was approved by the FDA for the treatment of unresectable or metastatic basal cell carcinomas of the skin.

Crizotinib for the treatment of patients with advanced non-small cell lung cancer.

Crizotinib is a potent small-molecule inhibitor of ALK tyrosine kinase receptor (anaplastic lymphoma kinase; ALK) and hepatocyte growth factor receptor (HGF receptor, proto-oncogene c-Met). A range of tumors, including subsets of non-small cell lung cancer (NSCLC), anaplastic large cell lymphoma and inflammatory myofibroblastic tumors harbor an ALK rearrangement that leads to oncogenic activation of ALK. Crizotinib has demonstrated preclinical and clinical activity against such malignancies through inhibition of ALK, and patients harboring ALK- rearranged NSCLC have demonstrated high response rates and prolonged progression-free survival in phase I and II studies. In August 2011, crizotinib was approved for the treatment of advanced ALK-positive NSCLC.

Multi-targeted tyrosine kinase inhibitors in clinical development: focus on XL-184 (cabozantinib).

XL-184 (cabozantinib) is a novel, small-molecule, multitargeted receptor tyrosine kinase inhibitor with particular activity against hepatocyte growth factor receptor (tyrosine-protein kinase Met), vascular endothelial growth factor receptor 2 (VEGFR-2) and proto-oncogene tyrosine-protein kinase receptor Ret. There is ample evidence of Met, VEGFR-2 and Ret signaling in several tumor types. Preclinical data suggest that XL-184 has activity in tumors derived from both epithelial and mesenchymal origins. Phase I and II clinical studies support significant antitumor activity, particularly in medullary thyroid cancer and cancers metastatic to the bone. This review will evaluate XL-184's preclinical pharmacology, pharmacokinetics, drug interactions and clinical activity in phase I through phase III studies.

Characterization of Rb uptake into Sf9 cells using cation chromatography: evidence for a K-Cl cotransporter.

To assess cation-chloride cotransporter activity in Sf9 cells, cation chromatography was used to measure initial uptake rates of Rb. Rb exchanged with cellular K, with 30% of cellular K replaced after a 40 min exposure to Rb. Rb uptake into Sf9 cells was not inhibited by 50 µmol l(-1) ouabain. Rb uptake was approximately 65% inhibited by 250 µmol l(-1) bumetanide added to the assay solution, and was more than 95% inhibited when cells were pre-incubated for 20 min with bumetanide (100 and 1000 µmol l(-1)). Uptake of Rb and Cl followed simple Michaelis-Menten kinetics, with a K(m) for Rb of 17.1+/-2.2 mmol l(-1) and a K(m) for Cl of 93.7+/-5.6 mmol l(-1). Rb uptake was not dependent upon extracellular Na. Two min exposures to solutions with reduced [Na] or [Cl] produced small but significant changes in cellular Na content. We conclude that the primary Rb uptake pathway in Sf9 cells is a K-Cl cotransporter and that cation chromatography can be used to effectively study kinetic parameters of cotransporter function in tissue culture cells. Characterization of baseline cation-chloride cotransporter activity in Sf9 cells strengthens their utility as a tool for expression and characterization of exogenous proteins.