Epigenetic scars of CD8+ T cell exhaustion persist after cure of chronic infection in humans.

T cell exhaustion is an induced state of dysfunction that arises in response to chronic infection and cancer. Exhausted CD8+ T cells acquire a distinct epigenetic state, but it is not known whether that chromatin landscape is fixed or plastic following the resolution of a chronic infection. Here we show that the epigenetic state of exhaustion is largely irreversible, even after curative therapy. Analysis of chromatin accessibility in HCV- and HIV-specific responses identifies a core epigenetic program of exhaustion in CD8+ T cells, which undergoes only limited remodeling before and after resolution of infection. Moreover, canonical features of exhaustion, including super-enhancers near the genes TOX and HIF1A, remain 'epigenetically scarred.' T cell exhaustion is therefore a conserved epigenetic state that becomes fixed and persists independent of chronic antigen stimulation and inflammation. Therapeutic efforts to reverse T cell exhaustion may require new approaches that increase the epigenetic plasticity of exhausted T cells.

Structural Alterations Driving Castration-Resistant Prostate Cancer Revealed by Linked-Read Genome Sequencing.

Nearly all prostate cancer deaths are from metastatic castration-resistant prostate cancer (mCRPC), but there have been few whole-genome sequencing (WGS) studies of this disease state. We performed linked-read WGS on 23 mCRPC biopsy specimens and analyzed cell-free DNA sequencing data from 86 patients with mCRPC. In addition to frequent rearrangements affecting known prostate cancer genes, we observed complex rearrangements of the AR locus in most cases. Unexpectedly, these rearrangements include highly recurrent tandem duplications involving an upstream enhancer of AR in 70%-87% of cases compared with <2% of primary prostate cancers. A subset of cases displayed AR or MYC enhancer duplication in the context of a genome-wide tandem duplicator phenotype associated with CDK12 inactivation. Our findings highlight the complex genomic structure of mCRPC, nominate alterations that may inform prostate cancer treatment, and suggest that additional recurrent events in the non-coding mCRPC genome remain to be discovered.

Hedgehog Pathway Inhibition.

The hedgehog (Hh) signaling pathway is aberrantly activated in a majority of basal cell carcinomas (BCC). Vismodegib and sonidegib are targeted inhibitors of Smoothened (SMO). Both drugs are approved for use in locally advanced BCC (laBCC), with vismodegib also approved for metastatic BCC (mBCC).

Adding 6 months of androgen deprivation therapy to postoperative radiotherapy for prostate cancer: a comparison of short-course versus no androgen deprivation therapy in the RADICALS-HD randomised controlled trial.

BACKGROUND: Previous evidence indicates that adjuvant, short-course androgen deprivation therapy (ADT) improves metastasis-free survival when given with primary radiotherapy for intermediate-risk and high-risk localised prostate cancer. However, the value of ADT with postoperative radiotherapy after radical prostatectomy is unclear. METHODS: RADICALS-HD was an international randomised controlled trial to test the efficacy of ADT used in combination with postoperative radiotherapy for prostate cancer. Key eligibility criteria were indication for radiotherapy after radical prostatectomy for prostate cancer, prostate-specific antigen less than 5 ng/mL, absence of metastatic disease, and written consent. Participants were randomly assigned (1:1) to radiotherapy alone (no ADT) or radiotherapy with 6 months of ADT (short-course ADT), using monthly subcutaneous gonadotropin-releasing hormone analogue injections, daily oral bicalutamide monotherapy 150 mg, or monthly subcutaneous degarelix. Randomisation was done centrally through minimisation with a random element, stratified by Gleason score, positive margins, radiotherapy timing, planned radiotherapy schedule, and planned type of ADT, in a computerised system. The allocated treatment was not masked. The primary outcome measure was metastasis-free survival, defined as distant metastasis arising from prostate cancer or death from any cause. Standard survival analysis methods were used, accounting for randomisation stratification factors. The trial had 80% power with two-sided α of 5% to detect an absolute increase in 10-year metastasis-free survival from 80% to 86% (hazard ratio [HR] 0·67). Analyses followed the intention-to-treat principle. The trial is registered with the ISRCTN registry, ISRCTN40814031, and ClinicalTrials.gov, NCT00541047. FINDINGS: Between Nov 22, 2007, and June 29, 2015, 1480 patients (median age 66 years [IQR 61-69]) were randomly assigned to receive no ADT (n=737) or short-course ADT (n=743) in addition to postoperative radiotherapy at 121 centres in Canada, Denmark, Ireland, and the UK. With a median follow-up of 9·0 years (IQR 7·1-10·1), metastasis-free survival events were reported for 268 participants (142 in the no ADT group and 126 in the short-course ADT group; HR 0·886 [95% CI 0·688-1·140], p=0·35). 10-year metastasis-free survival was 79·2% (95% CI 75·4-82·5) in the no ADT group and 80·4% (76·6-83·6) in the short-course ADT group. Toxicity of grade 3 or higher was reported for 121 (17%) of 737 participants in the no ADT group and 100 (14%) of 743 in the short-course ADT group (p=0·15), with no treatment-related deaths. INTERPRETATION: Metastatic disease is uncommon following postoperative bed radiotherapy after radical prostatectomy. Adding 6 months of ADT to this radiotherapy did not improve metastasis-free survival compared with no ADT. These findings do not support the use of short-course ADT with postoperative radiotherapy in this patient population. FUNDING: Cancer Research UK, UK Research and Innovation (formerly Medical Research Council), and Canadian Cancer Society.

Duration of androgen deprivation therapy with postoperative radiotherapy for prostate cancer: a comparison of long-course versus short-course androgen deprivation therapy in the RADICALS-HD randomised trial.

BACKGROUND: Previous evidence supports androgen deprivation therapy (ADT) with primary radiotherapy as initial treatment for intermediate-risk and high-risk localised prostate cancer. However, the use and optimal duration of ADT with postoperative radiotherapy after radical prostatectomy remains uncertain. METHODS: RADICALS-HD was a randomised controlled trial of ADT duration within the RADICALS protocol. Here, we report on the comparison of short-course versus long-course ADT. Key eligibility criteria were indication for radiotherapy after previous radical prostatectomy for prostate cancer, prostate-specific antigen less than 5 ng/mL, absence of metastatic disease, and written consent. Participants were randomly assigned (1:1) to add 6 months of ADT (short-course ADT) or 24 months of ADT (long-course ADT) to radiotherapy, using subcutaneous gonadotrophin-releasing hormone analogue (monthly in the short-course ADT group and 3-monthly in the long-course ADT group), daily oral bicalutamide monotherapy 150 mg, or monthly subcutaneous degarelix. Randomisation was done centrally through minimisation with a random element, stratified by Gleason score, positive margins, radiotherapy timing, planned radiotherapy schedule, and planned type of ADT, in a computerised system. The allocated treatment was not masked. The primary outcome measure was metastasis-free survival, defined as metastasis arising from prostate cancer or death from any cause. The comparison had more than 80% power with two-sided α of 5% to detect an absolute increase in 10-year metastasis-free survival from 75% to 81% (hazard ratio [HR] 0·72). Standard time-to-event analyses were used. Analyses followed intention-to-treat principle. The trial is registered with the ISRCTN registry, ISRCTN40814031, and ClinicalTrials.gov, NCT00541047. FINDINGS: Between Jan 30, 2008, and July 7, 2015, 1523 patients (median age 65 years, IQR 60-69) were randomly assigned to receive short-course ADT (n=761) or long-course ADT (n=762) in addition to postoperative radiotherapy at 138 centres in Canada, Denmark, Ireland, and the UK. With a median follow-up of 8·9 years (7·0-10·0), 313 metastasis-free survival events were reported overall (174 in the short-course ADT group and 139 in the long-course ADT group; HR 0·773 [95% CI 0·612-0·975]; p=0·029). 10-year metastasis-free survival was 71·9% (95% CI 67·6-75·7) in the short-course ADT group and 78·1% (74·2-81·5) in the long-course ADT group. Toxicity of grade 3 or higher was reported for 105 (14%) of 753 participants in the short-course ADT group and 142 (19%) of 757 participants in the long-course ADT group (p=0·025), with no treatment-related deaths. INTERPRETATION: Compared with adding 6 months of ADT, adding 24 months of ADT improved metastasis-free survival in people receiving postoperative radiotherapy. For individuals who can accept the additional duration of adverse effects, long-course ADT should be offered with postoperative radiotherapy. FUNDING: Cancer Research UK, UK Research and Innovation (formerly Medical Research Council), and Canadian Cancer Society.

Cabozantinib in patients with unresectable and progressive metastatic phaeochromocytoma or paraganglioma (the Natalie Trial): a single-arm, phase 2 trial.

BACKGROUND: Metastatic phaeochromocytomas and paragangliomas (MPPGs) are orphan diseases. Up to 50% of MPPGs are associated with germline pathogenic variants of the SDHB gene. These tumours and many non-familial MPPGs exhibit a phenotype that is characterised by abnormal angiogenesis. We aimed to assess the activity and safety of cabozantinib, an antiangiogenic multi-tyrosine kinase inhibitor, in patients with MPPGs. METHODS: The Natalie Trial is a single-arm, phase 2 clinical trial being conducted at The University of Texas MD Anderson Cancer Center (Houston, TX, USA). Patients aged 18 years or older with histologically confirmed, progressive, and unresectable MPPGs, with an Eastern Cooperative Oncology Group performance status of 0-2, were treated with oral cabozantinib 60 mg/day. The primary endpoint was the investigator-assessed overall response rate per the Response Evaluation Criteria in Solid Tumours version 1.1 criteria. All outcomes were assessed in all evaluable participants who received any amount of study treatment. The trial is registered with ClinicalTrials.gov (NCT02302833) and is active but not recruiting. FINDINGS: From March 10, 2015, to May 11, 2021, 17 patients (13 male participants and four female participants) were enrolled. The median follow-up was 25 months (IQR 18-49). The overall response rate was 25·0% (95% CI 7·3-52·4; four of 16 patients). Seven grade 3 adverse events were reported in six patients, including single cases of hand-and-foot syndrome, hypertension, rectal fistula, QT prolongation, and asymptomatic hypomagnesaemia, and two cases of asymptomatic elevations of amylase and lipase. There were no grade 4 adverse events and no patient died on-study. INTERPRETATION: Cabozantinib shows promising activity in patients with MPPGs. FUNDING: Team NAT Foundation, Margaret Cazalot, and Clarence P Cazalot.

Cabozantinib monotherapy for advanced adrenocortical carcinoma: a single-arm, phase 2 trial.

BACKGROUND: Adrenocortical carcinoma is a rare malignancy with poor response to systemic chemotherapy. Mitotane is the only approved therapy for adrenocortical carcinoma. Cabozantinib is a multikinase inhibitor approved in multiple malignancies. This is the first prospective trial to explore the anti-tumour activity, safety, and pharmacokinetic profile of cabozantinib in patients with advanced adrenocortical carcinoma. METHODS: This investigator-initiated, single-arm, phase 2 trial in adult patients (aged ≥18 years) with advanced adrenocortical carcinoma was done at the University of Texas MD Anderson Cancer Center (Houston, TX, USA). Eligible patients had histologically confirmed adrenocortical carcinoma, were not candidates for surgery with curative intent, had measurable disease, had an estimated life expectancy of at least 3 months, and an Eastern Cooperative Oncology Group (ECOG) performance status of 0-2 with adequate organ function. Patients who had used mitotane within 6 months of study participation were required to have a serum mitotane level of less than 2 mg/L. Patients were given oral cabozantinib 60 mg daily with the option of dose reduction to manage adverse events. The primary endpoint was progression-free survival at 4 months, assessed in all patients who received at least one dose of study drug per protocol. This study is registered with ClinicalTrials.gov, NCT03370718, and is now complete. FINDINGS: Between March 1, 2018, and May 31, 2021, we enrolled 18 patients (ten males and eight females), all of whom received at least one dose of study treatment. Of the 18 patients, eight (44%) had an ECOG performance status of 0, nine (50%) patients had a performance status of 1, and one (6%) patient had a performance status of 2. Median follow-up was 36·8 months (IQR 30·2-50·3). At 4 months, 13 (72·2%; 95% CI 46·5-90·3) of 18 patients had progression-free survival and median progression-free survival was 6 months (95% CI 4·3 to not reached). One patient remains on treatment. Treatment-related adverse events of grade 3 or worse occurred in 11 (61%) of 18 patients. The most common grade 3 adverse events were lipase elevation (three [17%] of 18 patients), elevated γ-glutamyl transferase concentrations (two [11%] patients), elevated alanine aminotransferase concentrations (two [11%] patients), hypophosphatemia (two [11%] patients), and hypertension (two [11%] patients). One (6%) of 18 patients had grade 4 hypertension. No treatment related deaths occurred on study. INTERPRETATION: Cabozantinib in advanced adrenocortical carcinoma showed promising efficacy with a manageable and anticipated safety profile. Further prospective studies with cabozantinib alone and in combination with immune checkpoint therapy are ongoing. FUNDING: Exelixis.

Hedgehog Inhibitors Beyond Clinical Complete Response in Basal Cell Carcinoma: Should I Stop or Should I Go?

INTRODUCTION: In advanced basal cell carcinoma (BCC), the issue of whether Hedgehog inhibitors (HHIs) should be stopped or not after clinical complete response (cCR) achievement remains an unmet clinical need. MATERIALS AND METHODS: We conducted a retrospective, multicenter study across 7 Italian dermato-oncology units including patients with BCC who continued vismodegib after cCR between 2012 and 2019. We assessed the relationship between the duration of vismodegib intake (days to cCR [DTCR], days to stop after cCR [DTS], total treatment days [TTD]), and disease-free survival (DFS). Reasons to stop vismodegib were (R1) toxicity and (R2) disease recurrence. The relationship between DTCR, DTS, TTD, and DFS in the whole population and in R1 subgroup was assessed by Pearson's correlation coefficient (P < .05) and Bayesian statistics (BF10). RESULTS: Sixty-eight BCC patients with a median (m) age of 75.5 years (39-100) were included. Most patients were male (N = 43, 63%), without Gorlin syndrome (N = 56, 82%) and with head and neck area as primary site (N = 51, 75%). After cCR, out of 68 patients, 90% (N = 61/68) discontinued vismodegib: 82% (N = 50/61) due to toxicity (R1), and 18% (N = 11/61) due to recurrence (R2). Conversely, 10% (N = 7/68) continued vismodegib until last follow-up. In the whole population (N = 68), cCR was achieved with a mDTCR of 180.50 days. DFS showed a significant correlation with DTS (P < .01, BF10 = 39.2) and TTD (P < .01, BF10 = 35566), while it was not correlated to DTCR (BF10 < 0.1). The analysis of R1 subgroup (N = 50) confirmed these results. DFS correlated with DTS in all recurrent patients (N = 38, r = 0.44, P < .01) and in the recurrent patients who stopped vismodegib for toxicity (N = 26, r = 0.665, P < .01). DFS was longer when vismodegib was maintained for >2 months after cCR (mDFS > 2 months, N = 54 vs. ≤ 2 months, N = 14: 470 vs. 175 d, P < .01). CONCLUSIONS: Our retrospective results suggest that HHIs should be continued after cCR to improve DFS in BCC.

Plasma ctDNA Monitoring of a PTCH1-Mutant Metastatic Adult Medulloblastoma Showing a Durable Benefit With Vismodegib.

Adult medulloblastoma (MB) is a rare disease affecting 0.6 persons per million adults over 19 years of age. The SHH-activated/TP53-wild type is the most common subtype, accounting for 60% of adult MBs, being characterized by mutations in PTCH1, SMO, or the TERT promoter. Several small studies demonstrate objective but short-lived responses to SMO inhibitors such as vismodegib or sonidegib. Like other oncogene-addicted solid tumors, detection of the corresponding drivers through liquid biopsy could aid in the molecular diagnosis and monitoring of the disease through less invasive procedures. However, most studies have only evaluated cerebrospinal fluid as the ctDNA reservoir, and very limited evidence exists on the role of liquid biopsy in plasma in patients with primary central nervous system tumors, including MB. We present the case of a 26-year-old patient with a recurrent MB, in which next-generation sequencing (FoundationOne CDx) revealed a mutation in PTCH1, allowing the patient to be treated with vismodegib in second line, resulting in a durable benefit lasting for 1 year. Using an in-house digital PCR probe, the PTCH1 mutation could be tracked in ctDNA during treatment with first-line chemotherapy and while on treatment with vismodegib, demonstrating a precise correlation with the radiological and clinical behavior of the disease.

A slow-cycling LGR5 tumour population mediates basal cell carcinoma relapse after therapy.

Basal cell carcinoma (BCC) is the most frequent cancer in humans and results from constitutive activation of the Hedgehog pathway1. Several Smoothened inhibitors are used to treat Hedgehog-mediated malignancies, including BCC and medulloblastoma2. Vismodegib, a Smoothened inhibitor, leads to BCC shrinkage in the majority of patients with BCC3, but the mechanism by which it mediates BCC regression is unknown. Here we used two genetically engineered mouse models of BCC4 to investigate the mechanisms by which inhibition of Smoothened mediates tumour regression. We found that vismodegib mediates BCC regression by inhibiting a hair follicle-like fate and promoting the differentiation of tumour cells. However, a small population of tumour cells persists and is responsible for tumour relapse following treatment discontinuation, mimicking the situation found in humans5. In both mouse and human BCC, this persisting, slow-cycling tumour population expresses LGR5 and is characterized by active Wnt signalling. Combining Lgr5 lineage ablation or inhibition of Wnt signalling with vismodegib treatment leads to eradication of BCC. Our results show that vismodegib induces tumour regression by promoting tumour differentiation, and demonstrates that the synergy between Wnt and Smoothened inhibitors is a clinically relevant strategy for overcoming tumour relapse in BCC.

A cell identity switch allows residual BCC to survive Hedgehog pathway inhibition.

Despite the efficacy of Hedgehog pathway inhibitors in the treatment of basal cell carcinoma (BCC)1, residual disease persists in some patients and may contribute to relapse when treatment is discontinued2. Here, to study the effect of the Smoothened inhibitor vismodegib on tumour clearance, we have used a Ptch1-Trp53 mouse model of BCC3 and found that mice treated with vismodegib harbour quiescent residual tumours that regrow upon cessation of treatment. Profiling experiments revealed that residual BCCs initiate a transcriptional program that closely resembles that of stem cells of the interfollicular epidermis and isthmus, whereas untreated BCCs are more similar to the hair follicle bulge. This cell identity switch was enabled by a mostly permissive chromatin state accompanied by rapid Wnt pathway activation and reprogramming of super enhancers to drive activation of key transcription factors involved in cellular identity. Accordingly, treatment of BCC with both vismodegib and a Wnt pathway inhibitor reduced the residual tumour burden and enhanced differentiation. Our study identifies a resistance mechanism in which tumour cells evade treatment by adopting an alternative identity that does not rely on the original oncogenic driver for survival.

Review of Targeted Therapy, Vismodegib, for the Treatment of Periocular Basal Cell Carcinoma.

PURPOSE: Periocular locally advanced basal cell carcinoma (POLA-BCC) is characterized by orbital involvement and/or extensive invasion of periocular structures. Hedgehog pathway inhibitors have been used for POLA-BCC with promising outcomes. METHODS: The authors reviewed 11 articles published in English literature from January 2012 to July 2022 and reported the outcomes of patients with POLA-BCC who were treated with vismodegib. RESULTS: A total of 384 patients were treated with vismodegib. The mean age was 72 years, and the median treatment duration was 9 months. The overall response rate was 75% with a median follow-up time of 14.4 months. Following vismodegib treatment, the median number of patients who required adjuvant surgery was 43% with a median time to surgery of 6.5 months. The exenteration rate was 6% (overall 8 patients). In total 93.7% of patients experienced grade I adverse events, 26.7% to 37.5% grade II, 8.8% to 10% grade III-IV, and 0.8% to 4.8% grade V. Major side effects included dysgeusia (30-100%), muscle spasm (15-100%), alopecia (47-75%), weight loss (23-83%), and decreased appetite (19-42%). The median percentage of patients who discontinued treatment due to toxicity was 29% with a median interval of 5 months before the development of side effects. The median recurrence rate following discontinuation of vismodegib was 7.8% with a median recurrence duration of 20 months. CONCLUSIONS: In patients with POLA-BCC, vismodegib, a hedgehog pathway inhibitor, provided high rates of orbital preservation, reducing exenteration rates to 6%. Neoadjuvant therapy with vismodegib can also be suggested for patients with POLA-BCC. While extremely effective, side effects lead to temporary or permanent discontinuation of vismodegib in small numbers of patients.

AGA Clinical Practice Guideline on Systemic Therapy for Hepatocellular Carcinoma.

BACKGROUND & AIMS: Hepatocellular carcinoma (HCC), the most common primary liver cancer, remains a deadly cancer, with an incidence that has tripled in the United States since 1980. In recent years, new systemic therapies for HCC have been approved and a critical assessment of the existing data is necessary to balance benefits and harms and inform the development of evidence-based guidelines. METHODS: The American Gastroenterological Association formed a multidisciplinary group consisting of a Technical Review Panel and a Guideline Panel. The Technical Review Panel prioritized clinical questions and outcomes according to their importance for clinicians and patients and conducted an evidence review of systemic therapies in patients with advanced-stage HCC. The Grading of Recommendations Assessment, Development and Evaluation framework was used to assess evidence. The Guideline Panel reviewed the evidence and used the Evidence-to-Decision Framework to develop recommendations. RESULTS: The Panel reviewed the evidence, summarized in the Technical Review, for the following medications approved by the US Food and Drug Administration for HCC: first-line therapies: bevacizumab+atezolizumab, sorafenib, and lenvatinib; second-line therapies: cabozantinib, pembrolizumab, ramucirumab, and regorafenib; and other agents: bevacizumab, nivolumab, and nivolumab+ipilimumab. CONCLUSIONS: The Panel agreed on 11 recommendations focused on systemic therapy for HCC in patients who are not eligible for locoregional therapy or resection, those with metastatic disease and preserved liver function, those with poor liver function, and those on systemic therapy as adjuvant therapy.

Effective combinatorial immunotherapy for castration-resistant prostate cancer.

A significant fraction of patients with advanced prostate cancer treated with androgen deprivation therapy experience relapse with relentless progression to lethal metastatic castration-resistant prostate cancer (mCRPC). Immune checkpoint blockade using antibodies against cytotoxic-T-lymphocyte-associated protein 4 (CTLA4) or programmed cell death 1/programmed cell death 1 ligand 1 (PD1/PD-L1) generates durable therapeutic responses in a significant subset of patients across a variety of cancer types. However, mCRPC showed overwhelming de novo resistance to immune checkpoint blockade, motivating a search for targeted therapies that overcome this resistance. Myeloid-derived suppressor cells (MDSCs) are known to play important roles in tumour immune evasion. The abundance of circulating MDSCs correlates with prostate-specific antigen levels and metastasis in patients with prostate cancer. Mouse models of prostate cancer show that MDSCs (CD11b+Gr1+) promote tumour initiation and progression. These observations prompted us to hypothesize that robust immunotherapy responses in mCRPC may be elicited by the combined actions of immune checkpoint blockade agents together with targeted agents that neutralize MDSCs yet preserve T-cell function. Here we develop a novel chimaeric mouse model of mCRPC to efficiently test combination therapies in an autochthonous setting. Combination of anti-CTLA4 and anti-PD1 engendered only modest efficacy. Targeted therapy against mCRPC-infiltrating MDSCs, using multikinase inhibitors such as cabozantinib and BEZ235, also showed minimal anti-tumour activities. Strikingly, primary and metastatic CRPC showed robust synergistic responses when immune checkpoint blockade was combined with MDSC-targeted therapy. Mechanistically, combination therapy efficacy stemmed from the upregulation of interleukin-1 receptor antagonist and suppression of MDSC-promoting cytokines secreted by prostate cancer cells. These observations illuminate a clinical path hypothesis for combining immune checkpoint blockade with MDSC-targeted therapies in the treatment of mCRPC.

Use of Cabozantinib to Treat MET -amplified Pediatric Colorectal Cancer.

Pediatric colorectal cancer (CRC) is extremely rare, with little information about genetic profiles compared with adult CRC. Here, a 13-year-old male with advanced CRC underwent cancer gene panel testing, which detected 4 genetic abnormalities ( MET amplification in addition to TP53 , SMAD4 , and CTNNA1 mutations) that might be associated with a poor prognosis. Based on high-level MET amplification, he received a multikinase inhibitor, cabozantinib, after failure of first-line and second-line chemotherapy, resulting in transient disease stabilization. Tailored targeted therapy based on molecular profiling can be an effective treatment strategy for rare cancers such as pediatric CRC.

Real-World Experience with Vismodegib on Advanced and Multiple BCCs: Data from the RELIVIS Study.

BACKGROUND: Vismodegib is approved for advanced cases of basal cell carcinomas not amenable to surgery or radiotherapy. Large studies on the use of vismodegib in clinical practice are scarce. OBJECTIVES: The main objective of the study was to analyse the evolution and therapeutic management of relapses and lack of response in patients who had received vismodegib for locally advanced and/or multiple basal cell carcinomas in a real-life multicentre setting. METHODS: This nationwide retrospective study collected data on patients treated with vismodegib in 15 specialized centres. We included patients who first received vismodegib until intolerable toxicity, maximum response, or progressive disease. Exploratory research variables referred to patient and tumour characteristics, vismodegib effectiveness and safety, relapse rate and management, and mortality. A multivariable logistic regression model was used to identify predictors of complete clinical response. RESULTS: 133 patients with advanced BCC were included in the registry. The objective response rate (ORR) was 77.5% and nearly half of the patients (45.9%) achieved complete remission. Long-term information and detailed information of subsequent treatments after a regime of vismodegib was available for 115 patients. Only 34% of the patients in this group were subsequently treated with other therapies or vismodegib rechallenge. Sixty-nine percent of the patients who had shown a complete remission with vismodegib remained free of recurrence while 30.7% relapsed. Almost half of the patients who received additional therapies after the first course of vismodegib achieved complete tumour remission. Three and 2 out of 9 patients who were rechallenged with vismodegib achieved complete and partial responses, respectively, with an ORR of 55.5%. CONCLUSION: Our study confirms efficacy of vismodegib in routine clinical practice. The risk of recurrence after achieving complete response with vismodegib was lower than previous reports. Rechallenge with vismodegib is feasible and most patients responded to re-treatment.

Quantitative determination of plasma cabozantinib concentration using HPLC-UV and its application to patients with renal cell carcinoma.

Cabozantinib is an oral small-molecule tyrosine kinase inhibitor that has become a standard of care for advanced renal cell carcinoma (RCC). However, cabozantinib is associated with a high rate of adverse events. Therefore, individualised cabozantinib administration and monitoring could help maximise its therapeutic efficacy and avoid serious adverse events. This study developed and validated a method to determine cabozantinib concentration in plasma using HPLC-UV. Sorafenib, an internal standard, was added to the plasma sample containing cabozantinib. A calibration curve for cabozantinib showed good linearity (R2 = 1.00), between 25 and 4,000 ng/ml. The recovery rate was above 92.1%, and the intra- and inter-day coefficients of variation were smaller than 5.2 and 6.8%, respectively. Then, we applied the method for monitoring cabozantinib blood levels in three patients with advanced RCC who were taking cabozantinib at a dose of 20, 40 or 60 mg/day. Grade 3 adverse events were more likely to occur in patients with high dosing and blood level of cabozantinib. Owing to its simplicity, the developed method can be used in general hospitals, and is expected to help maximise drug efficacy and minimise serious adverse events in many patients with RCC undergoing cabozantinib treatment.

An In Vitro Analysis of TKI-Based Sequence Therapy in Renal Cell Carcinoma Cell Lines.

The tyrosine kinase inhibitor (TKI) cabozantinib might impede the growth of the sunitinib-resistant cell lines by targeting MET and AXL overexpression in metastatic renal cell carcinoma (mRCC). We studied the role of MET and AXL in the response to cabozantinib, particularly following long-term administration with sunitinib. Two sunitinib-resistant cell lines, 786-O/S and Caki-2/S, and the matching 786-O/WT and Caki-2/WT cells were exposed to cabozantinib. The drug response was cell-line-specific. The 786-O/S cells were less growth-inhibited by cabozantinib than 786-O/WT cells (p-value = 0.02). In 786-O/S cells, the high level of phosphorylation of MET and AXL was not affected by cabozantinib. Despite cabozantinib hampering the high constitutive phosphorylation of MET, the Caki-2 cells showed low sensitivity to cabozantinib, and this was independent of sunitinib pretreatment. In both sunitinib-resistant cell lines, cabozantinib increased Src-FAK activation and impeded mTOR expression. The modulation of ERK and AKT was cell-line-specific, mirroring the heterogeneity among the patients. Overall, the MET- and AXL-driven status did not affect cell responsiveness to cabozantinib in the second-line treatment. The activation of Src-FAK might counteract cabozantinib activity and contribute to tumor survival and may be considered an early indicator of therapy response.

Cabozantinib in combination with atezolizumab in patients with metastatic castration-resistant prostate cancer: results from an expansion cohort of a multicentre, open-label, phase 1b trial (COSMIC-021).

BACKGROUND: Patients with metastatic castration-resistant prostate cancer have few treatment options after novel hormonal therapy (eg, abiraterone or enzalutamide). We aimed to evaluate cabozantinib, a tyrosine kinase inhibitor with immunomodulatory properties, in combination with the PD-L1 inhibitor atezolizumab in metastatic castration-resistant prostate cancer. METHODS: COSMIC-021 is an ongoing, multicentre, open-label, phase 1b study with a dose-escalation stage followed by tumour-specific expansion stages. Expansion cohort 6 in metastatic castration-resistant prostate cancer was enrolled at 42 cancer research centres in France, Italy, the Netherlands, Spain, and the USA. Eligible patients were aged 18 years or older and had metastatic castration-resistant prostate cancer with radiographic soft tissue progression following treatment with either enzalutamide or abiraterone, or both; measurable soft tissue disease per Response Evaluation Criteria In Solid Tumours (RECIST) version 1.1; and an Eastern Cooperative Oncology Group performance status of 0 or 1. Patients received oral cabozantinib 40 mg per day and intravenous atezolizumab 1200 mg once every 3 weeks. Study treatment continued until progressive disease or unacceptable toxicity. All enrolled patients were assessed for efficacy and safety. The primary endpoint was objective response rate per RECIST version 1.1 as assessed by the investigator. This study is registered with ClinicalTrials.gov, NCT03170960. FINDINGS: Between April 24, 2018, and Aug 31, 2020, 132 patients were enrolled and received at least one dose of study treatment. At data cutoff (Feb 19, 2021), median duration of follow-up was 15·2 months (IQR 9·6-21·7). Objective response rate was 23% (95% CI 17-32; 31 of 132 patients), with three (2%) confirmed complete responses and 28 (21%) confirmed partial responses. 72 (55%) of 132 patients had grade 3-4 treatment-related adverse events, with the most common being pulmonary embolism (11 [8%] patients), diarrhoea (nine [7%]), fatigue (nine [7%]), and hypertension (nine [7%]). There was one grade 5 treatment-related adverse event (dehydration). 74 (56%) of 132 patients had serious adverse events of any causality. 28 (21%) of 132 patients had treatment-related adverse events leading to discontinuation of either study drug. INTERPRETATION: Cabozantinib plus atezolizumab showed promising antitumour activity in patients with metastatic castration-resistant prostate cancer after novel hormonal therapy with an acceptable safety profile, supporting further evaluation of this combination. FUNDING: Exelixis.

Cabozantinib-nivolumab sequence in metastatic renal cell carcinoma: The CABIR study.

Nivolumab and cabozantinib are approved agents in mRCC patients after sunitinib/pazopanib (TKI) failure. However, the optimal sequence, cabozantinib then nivolumab (CN) or nivolumab then cabozantinib (NC), is still unknown. The CABIR study aimed to identify the optimal sequence between CN and NC after frontline VEGFR-TKI. In this multicenter retrospective study, we collected data from mRCC pts receiving CN or NC, after frontline VEGFR-TKI. A propensity score (PrS) was calculated to manage bias selection, and sequence comparisons were carried out with a cox model on a matched sample 1:1. The primary endpoint was progression-free survival (PFS) from the start of second line to progression in third line (PFS2-3 ). Key secondary endpoints included overall survival from second line (OS2 ). Out of 139 included mRCC patients, 38 (27%) and 101 (73%) received CN and NC, respectively. Overlap in PrS allowed 1:1 matching for each CN pts, with characteristics well balanced. For both PFS2-3 and OS2 , NC sequence was superior to CN (PFS2-3 : HR = 0.58 [0.34-0.98], P = .043; OS2 : 0.66 [0.42-1.05], P = .080). Superior PFS2-3 was in patients treated between 6 and 18 months with prior VEGFR-TKI (P = .019) and was driven by a higher PFSL3 with cabozantinib when given after nivolumab (P < .001). The CABIR study shows a prolonged PFS of the NC sequence compared to CN in mRCC after first line VEGFR-TKI failure. The data suggest that cabozantinib may be more effective than nivolumab in the third-line setting, possibly related to an ability of cabozantinib to overcome resistance to PD-1 blockade.