Dostarlimab or pembrolizumab plus chemotherapy in previously untreated metastatic non-squamous non-small cell lung cancer: the randomized PERLA phase II trial

PERLA is a global, double-blind, parallel phase II trial (NCT04581824) comparing efficacy and safety of anti-PD-1 antibodies dostarlimab and pembrolizumab, plus chemotherapy (DCT and PCT, respectively) as first-line treatment in patients with metastatic non-squamous NSCLC without known targetable genomic aberrations. Patients stratified by PD-L1 tumor proportion score and smoking status were randomized 1:1, receiving ≤35 cycles 500 mg dostarlimab or 200 mg pembrolizumab, ≤35 cycles 500 mg/m2 pemetrexed and ≤4 cycles cisplatin (75 mg/m2) or carboplatin (AUC 5 mg/ml/min) Q3W. Primary endpoint was overall response rate (ORR) (blinded independent central review). Secondary endpoints include progression-free survival (PFS) based on investigator assessment, overall survival (OS) and safety. Exploratory endpoints include ORR by PD-L1 subgroup and duration of response. PERLA met its pre-specified endpoint. ORR (n/N; 95% CI) is 45% (55/121; 36.4-54.8) for DCT and 39% (48/122; 30.6-48.6) for PCT (data cut-off: 07 July 23), numerically favoring dostarlimab in PD-L1-positive subgroups. Median PFS (months [95% CI]) is 8.8 (6.7-10.4) for DCT and 6.7 (4.9-7.1) for PCT (HR 0.70 [95% CI: 0.50-0.98]; data cut-off: 04 August 22). Median OS (months [95% CI]) is 19.4 (14.5-NR) for DCT and 15.9 (11.6-19.3) for PCT (HR 0.75 [95% CI: 0.53-1.05]) (data cut-off: 07 July 23). Safety profiles are similar between groups. In this study, DCT shows similar efficacy to PCT and demonstrates clinical efficacy as first-line treatment for patients with metastatic non-squamous NSCLC.

A phase I study of capivasertib in combination with abiraterone acetate in patients with metastatic castration-resistant prostate cancer

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Background: Androgen receptor (AR) targeting therapies prolong survival of patients with metastatic castration-resistant prostate cancer (mCRPC); however, in many cases, resistance develops, resulting in disease progression. Activation of the PI3K/AKT/mTOR signaling pathway is common in mCRPC and contributes to resistance, mostly due to loss of PTEN, which occurs in 40–60% of patients. Preclinical studies have demonstrated reciprocal regulation between the AR and PI3K/AKT/mTOR pathways and significant anti-tumor activity when both pathways are inhibited, particularly in models with PTEN-loss. Thus, a rationale exists to inhibit both pathways in mCRPC patients. We report interim results of a phase 1 multicohort study (NCT04087174) to confirm the acceptable dose of capivasertib, a potent, selective pan-AKT inhibitor in combination with the androgen synthesis inhibitor abiraterone acetate (AA) in mCRPC patients. Methods: Patients who had received at least one prior systemic therapy (chemotherapy or novel hormonal agent) for mCRPC were given AA (1000 mg, once daily) with capivasertib (400 mg, twice daily, 4 days on/3 days off) until unacceptable toxicity or disease progression. Dose-limiting toxicity in the first 28 days of treatment and adverse events were recorded. Results: 15 patients, median age 67 (range 49–82) years, were recruited in the USA and Spain. Twelve patients had received prior chemotherapy; 7 had two or more prior lines. Seven patients had received prior AA and 10 had received prior enzalutamide. No dose-limiting toxicities were recorded. Eight patients reported at least one grade ≥ 3 adverse event (AE). Grade ≥ 3 AEs in 7 patients were related to capivasertib: allergic reaction to medication, asthenia, type 2 diabetes mellitus, diarrhea and fatigue were each reported in 1 patient, maculopapular rash − in 2 patients, both hypokalemia and acquired Fanconi syndrome − in 1 patient. Acute kidney injury was reported in 4 patients but was not considered related to capivasertib. The most common AEs of any grade related to capivasertib were: diarrhea, 6/15 patients (40%); maculopapular rash, 5/15 (33%); fatigue, 4/15 (27%); hyperglycemia/type 2 diabetes mellitus, 4/15 (27%); nausea, 3/15 (20%); hypokalemia, 2/15 (13%); hypophosphatemia, 2/15 (13%). Capivasertib was discontinued in 4/15 patients (27%) due to AEs. Between initial screening and day 29 of treatment, 5 patients had reduced (> 20%) PSA levels, with 3 patients showing sustained falls in PSA over 12 weeks. Conclusions: In this phase 1 study combined capivasertib and AA exhibits an acceptable safety and tolerability profile. Further data on the clinical efficacy and safety of the combination are being collected in the phase 3 CAPItello-281 trial. Acknowledgments: We thank Adam Errington, PhD, of Oxford PharmaGenesis, for medical writing assistance. Funding: This trial is funded by AstraZeneca. Clinical trial information: NCT04087174.

Development and validation for research assessment of Oncotype DX® Breast Recurrence Score, EndoPredict® and Prosigna®

Multi-gene prognostic signatures including the Oncotype® DX Recurrence Score (RS), EndoPredict® (EP) and Prosigna® (Risk Of Recurrence, ROR) are widely used to predict the likelihood of distant recurrence in patients with oestrogen-receptor-positive (ER+), HER2-negative breast cancer. Here, we describe the development and validation of methods to recapitulate RS, EP and ROR scores from NanoString expression data. RNA was available from 107 tumours from postmenopausal women with early-stage, ER+, HER2- breast cancer from the translational Arimidex, Tamoxifen, Alone or in Combination study (TransATAC) where previously these signatures had been assessed with commercial methodology. Gene expression was measured using NanoString nCounter. For RS and EP, conversion factors to adjust for cross-platform variation were estimated using linear regression. For ROR, the steps to perform subgroup-specific normalisation of the gene expression data and calibration factors to calculate the 46-gene ROR score were assessed and verified. Training with bootstrapping (n = 59) was followed by validation (n = 48) using adjusted, research use only (RUO) NanoString-based algorithms. In the validation set, there was excellent concordance between the RUO scores and their commercial counterparts (rc(RS) = 0.96, 95% CI 0.93-0.97 with level of agreement (LoA) of -7.69 to 8.12; rc(EP) = 0.97, 95% CI 0.96-0.98 with LoA of -0.64 to 1.26 and rc(ROR) = 0.97 (95% CI 0.94-0.98) with LoA of -8.65 to 10.54). There was also a strong agreement in risk stratification: (RS: κ = 0.86, p < 0.0001; EP: κ = 0.87, p < 0.0001; ROR: κ = 0.92, p < 0.001). In conclusion, the calibrated algorithms recapitulate the commercial RS and EP scores on individual biopsies and ROR scores on samples based on subgroup-centreing method using NanoString expression data.

Efficacy of Savolitinib vs Sunitinib in Patients With MET-Driven Papillary Renal Cell Carcinoma: The SAVOIR Phase 3 Randomized Clinical Trial

Importance

Papillary renal cell carcinoma (PRCC) is the most common type of non-clear cell RCC. Because some cases of PRCC are MET-driven, MET inhibition could be a targeted treatment approach. In previous studies, savolitinib (AZD6094, HMPL-504, volitinib), a highly selective MET-tyrosine kinase inhibitor, demonstrated antitumor activity in this patient group.

Objective

To determine whether savolitinib is a better treatment option for this patient population, vs standard of care, sunitinib.

Design, Setting, and Participants

The SAVOIR phase 3, open-label, randomized clinical trial was a multicenter study carried out in 32 centers in 7 countries between July 2017 and the data cutoff in August 2019. Overall, 360 to 450 patients were to be screened to randomize approximately 180 patients. Patients were adults with MET-driven (centrally confirmed), metastatic PRCC, with 1 or more measurable lesions. Exclusion criteria included prior receipt of sunitinib or MET inhibitor treatment. Overall, 254 patients were screened.

Interventions

Patients received 600 mg of savolitinib orally once daily (qd), or 50 mg of sunitinib orally qd for 4 weeks, followed by 2 weeks without treatment.

Main Outcomes and Measures

The primary end point was progression-free survival (PFS, assessed by investigator and confirmed by blinded independent central review). Secondary end points included overall survival (OS), objective response rate (ORR), duration of response, and safety/tolerability.

Results

At data cutoff, 60 patients were randomized (savolitinib n = 33; sunitinib n = 27); most patients had chromosome 7 gain (savolitinib, 30 [91%]; sunitinib, 26 [96%]) and no prior therapy (savolitinib, 28 [85%]; sunitinib, 25 [93%]). For savolitinib and sunitinib, 4 (12%) and 10 (37%) patients were women, and the median (range) age was 60 (23-78) and 65 (31-77) years, respectively. Following availability of external data on PFS with sunitinib in patients with MET-driven disease, study enrollment was closed. Progression-free survival, OS, and ORR were numerically greater with savolitinib vs sunitinib. Median PFS was not statistically different between the 2 groups: 7.0 months (95% CI, 2.8-not calculated) for savolitinib and 5.6 months (95% CI, 4.1-6.9) for sunitinib (hazard ratio [HR], 0.71; 95% CI, 0.37-1.36; P = .31). For savolitinib and sunitinib respectively, grade 3 or higher adverse events (AEs) were reported in 14 (42%) and 22 (81%) of patients and AE-related dose modifications in 10 (30%) and 20 (74%). After discontinuation, 12 (36%) and 5 (19%) of patients on savolitinib and sunitinib respectively, received subsequent anticancer therapy.

Conclusions and Relevance

Although patient numbers and follow-up were limited, savolitinib demonstrated encouraging efficacy vs sunitinib, with fewer grade 3 or higher AEs and dose modifications. Further investigation of savolitinib as a treatment option for MET-driven PRCC is warranted.

Trial Registration

ClinicalTrials.gov Identifier: NCT03091192.

SAVOIR: A phase III study of savolitinib versus sunitinib in pts with MET-driven papillary renal cell carcinoma (PRCC)

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Background: PRCC is the most common type of non-clear cell RCC, accounting for 10–15% of renal malignancies. As a subset of PRCC cases are MET-driven, MET inhibition may be an appropriate targeted treatment approach. In a single-arm Phase II study, savolitinib (AZD6094, HMPL‐504, volitinib), a highly selective MET-tyrosine kinase inhibitor, demonstrated antitumor activity in pts with MET-driven PRCC (Choueiri et al. JCO 2017). The Phase III SAVOIR study (NCT03091192) further assessed savolitinib vs standard of care sunitinib in pts with MET-driven PRCC. Methods: In this open-label (sponsor blinded), randomized study, pts with centrally confirmed MET-driven ( MET and/or HGF amplification, chromosome 7 gain and/or MET kinase domain mutations), metastatic PRCC were randomized to savolitinib 600 mg once daily (QD), or sunitinib 50 mg QD 4 weeks on / 2 weeks off. Primary objective was progression-free survival (PFS; RECIST 1.1 by blinded independent central review). Secondary objectives included overall survival (OS), objective response rate (ORR), and safety and tolerability. Results: After external data on predicted PFS with sunitinib in pts with MET-driven disease became available, study enrollment was closed. At data cutoff (Aug 2019), only 60 of the planned 180 pts were randomized (savolitinib n = 33; sunitinib n = 27). Most had chromosome 7 gain (savolitinib 91%; sunitinib 96%) and no prior therapy (savolitinib 85%; sunitinib 93%). PFS, OS, and ORR were numerically improved with savolitinib vs sunitinib (Table). CTCAE grade ≥3 adverse events (AEs) were reported in 42% and 81% of pts; dose modifications were related to AEs in 30% and 74% of pts with savolitinib and sunitinib respectively. After discontinuation, 36% of all savolitinib and 19% of all sunitinib pts received subsequent anticancer therapy. Conclusions: Although pt numbers and follow-up were limited, savolitinib demonstrated encouraging efficacy and an improved safety profile vs sunitinib, with fewer grade ≥3 AEs and fewer dose modifications required. Sunitinib performance was poorer than expected based on external retrospective data. Further investigation of savolitinib as a treatment option for MET-driven PRCC is warranted. Clinical trial information: NCT03091192 . [Table: see text]

Dissecting the predictive value of MAPK/AKT/estrogen-receptor phosphorylation axis in primary breast cancer to treatment response for tamoxifen over exemestane: a Translational Report of the Intergroup Exemestane Study (IES)-PathIES

PURPOSE

The prognostic and predictive values of the MAPK/AKT/ERα phosphorylation axis (pT202/T204MAPK, pT308AKT, pS473AKT, pS118ERα and pS167ERα) in primary tumours were assessed to determine whether these markers can differentiate between patient responses for switching adjuvant endocrine therapy after 2-3 years from tamoxifen to exemestane and continued tamoxifen monotherapy in the Intergroup Exemestane Study (IES).

METHODS

Of the 4724 patients in IES, 1506 were managed in a subset of centres (N = 89) participating in PathIES. These centres recruited 1282 (85%, 1282/1506) women into PathIES of whom 1036 had phospho-marker data. All phospho-markers were analysed by immunohistochemistry staining. Multivariable Cox proportional hazards models of the phospho-markers for disease-free survival (DFS) and overall survival (OS) were adjusted for clinicopathological factors. Treatment effects on the biomarker expression were determined by interaction tests. Benjamini-Hochberg adjustment for multiple testing with a false discovery rate of 10% was applied (pBH).

RESULTS

Phospho-T202/T204MAPK, pS118ERα and pS167ERα were all found to be correlated (pBH = 0.0002). These markers were not associated with either DFS or OS when controlling for the established clinicopathological factors. Interaction terms between the phospho-markers and treatment strategies for either DFS or OS were not statistically significant (pBH > 0.05 for all).

CONCLUSIONS

This PathIES study confirmed previously described associations between the phosphorylation site markers of AKT, MAPK and ERα activity in postmenopausal breast cancer patients. No prognostic correlations between the phosphorylation markers and clinical outcome were found, nor were they predictive for clinical outcomes among patients who switched therapy over those treated with tamoxifen alone.

Ki67 Is an Independent Predictor of Recurrence in the Largest Randomized Trial of 3 Radiation Fractionation Schedules in Localized Prostate Cancer

PURPOSE

To assess whether the cellular proliferation marker Ki67 provides prognostic information and predicts response to radiation therapy fractionation in patients with localized prostate tumors participating in a randomized trial of 3 radiation therapy fractionation schedules (74 Gy/37 fractions vs 60 Gy/20 fractions vs 57 Gy/19 fractions).

METHODS AND MATERIALS

A matched case-control study design was used; patients with biochemical/clinical failure >2 years after radiation therapy (BCR) were matched 1:1 to patients without recurrence using established prognostic factors (Gleason score, prostate-specific antigen, tumor stage) and fractionation schedule. Immunohistochemistry was used to stain diagnostic biopsy specimens for Ki67, which were scored using the unweighted global method. Conditional logistic regression models estimated the prognostic value of mean and maximum Ki67 scores on BCR risk. Biomarker-fractionation interaction terms determined whether Ki67 was predictive of BCR by fractionation.

RESULTS

Using 173 matched pairs, the median for mean and maximum Ki67 scores were 6.6% (interquartile range, 3.9%-9.8%) and 11.0% (interquartile range, 7.0%-15.0%) respectively. Both scores were significant predictors of BCR in models adjusted for established prognostic factors. Conditioning on matching variables and age, the odds of BCR were estimated to increase by 9% per 1% increase in mean Ki67 score (odds ratio 1.09; 95% confidence interval 1.04-1.15, P = .001). Interaction terms between Ki67 and fractionation schedules were not statistically significant.

CONCLUSIONS

Diagnostic Ki67 did not predict BCR according to fractionation schedule in CHHiP; however, it was a strong independent prognostic factor for BCR.

Assessment of Ki67 in relation to radiotherapy (RT) fractionation and prognosis in the CHHiP (CRUK/06/016) trial

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Background: A uniform fractionation schedule is used to deliver external beam RT for localised prostate tumours Individualising fractionation according to tumour biology may improve outcomes. In addition recurrence rates after RT vary considerably and better prognostic markers are needed to guide treatment choices. This study aims to identify if the cell proliferation marker Ki67 predicts response to RT fractionation in CHHiP, a randomised trial of 3 RT fractionation schedules. It also aims to identify if Ki67 predicts prognosis. Methods: A matched case:control study design was used, patients with biochemical or clinical failure > 2 years after RT (BCR) were matched to patients without recurrence according to established prognostic factors (Gleason score, PSA, Tumour-stage) and fractionation schedule. Immunohistochemical (IHC) staining of diagnostic biopsy sections was carried out using the MIB1 Ki67 antibody. Two independent investigators scored Ki67 using the unweighted global method (1) to derive a mean and maximum percentage of cells staining positive (mean Ki67 and maximum Ki67 respectively). Conditional logistic regression models were fitted with interaction terms between the biomarker and the fractionation schedules to determine whether Ki67 predicted BCR according to fractionation. Secondly models were fitted using the entire case:control study sample to estimate the prognostic value of Ki67 on risk of BCR. Results: Ki67 results were available for 173 matched pairs. The interaction terms between Ki67 and the fractionation schedules were not significant. However mean and maximum Ki67 were significant prognostic markers for BCR in a model adjusted for established prognostic factors. Conditioning on matching variables and age, the odds of BCR is estimated to increase by 9% per 1 point increase in mean Ki67 (OR = 1.09, 95%CI:1.04–1.15, p = 0.001). Conclusions: Ki67 did not predict BCR according to fractionation schedule in CHHiP, however it did predict prognosis independently of established prognostic factors. Additional IHC biomarkers are under evaluation.

Influence of inositol pyrophosphates on cellular energy dynamics

With its high-energy phosphate bonds, adenosine triphosphate (ATP) is the main intracellular energy carrier. It also functions in most signaling pathways, as a phosphate donor or a precursor for cyclic adenosine monophosphate. We show here that inositol pyrophosphates participate in the control of intracellular ATP concentration. Yeasts devoid of inositol pyrophosphates have dysfunctional mitochondria but, paradoxically, contain four times as much ATP because of increased glycolysis. We demonstrate that inositol pyrophosphates control the activity of the major glycolytic transcription factor GCR1. Thus, inositol pyrophosphates regulate ATP concentration by altering the glycolytic/mitochondrial metabolic ratio. Metabolic reprogramming through inositol pyrophosphates is an evolutionary conserved mechanism that is also preserved in mammalian systems.

Preparation of quality inositol pyrophosphates

Myo-inositol is present in nature either unmodified or in more complex phosphorylated derivates. Of the latest, the two most abundant in eukaryotic cells are inositol pentakisphosphate (IP(5;)) and inositol hexakisphosphate (phytic acid or IP(6;)). IP(5;) and IP(6;) are the precursors of inositol pyrophosphate molecules that contain one or more pyrophosphate bonds(1). Phosphorylation of IP(6;) generates diphoshoinositolpentakisphosphate (IP(7;) or PP-IP(5;)) and bisdiphoshoinositoltetrakisphosphate (IP(8;) or (PP)(2;)-IP(4;)). Inositol pyrophosphates have been isolated from all eukaryotic organisms so far studied. In addition, the two distinct classes of enzymes responsible for inositol pyrophosphate synthesis are highly conserved throughout evolution(2-4). The IP(6;) kinases (IP(6;)Ks) posses an enormous catalytic flexibility, converting IP(5;) and IP(6;) to PP-IP(4;) and IP(7;) respectively and subsequently, by using these products as substrates, promote the generation of more complex molecules(5,6). Recently, a second class of pyrophosphate generating enzymes was identified in the form of the yeast protein VIP(1;) (also referred as PP-IP(5;)K), which is able to convert IP(6;) to IP(7;) and IP(8;)(7,8). Inositol pyrophosphates regulate many disparate cellular processes such as insulin secretion(9), telomere length(10,11), chemotaxis(12), vesicular trafficking(13), phosphate homeostasis(14) and HIV-1 gag release(15). Two mechanisms of actions have been proposed for this class of molecules. They can affect cellular function by allosterically interacting with specific proteins like AKT(16). Alternatively, the pyrophosphate group can donate a phosphate to pre-phosphorylated proteins(17). The enormous potential of this research field is hampered by the absence of a commercial source of inositol pyrophosphates, which is preventing many scientists from studying these molecules and this new post-translational modification. The methods currently available to isolate inositol pyrophosphates require sophisticated chromatographic apparatus(18,19). These procedures use acidic conditions that might lead to inositol pyrophosphate degradation(20) and thus to poor recovery. Furthermore, the cumbersome post-column desalting procedures restrict their use to specialized laboratories. In this study we describe an undemanding method for the generation, isolation and purification of the products of the IP(6;)-kinase and PP-IP(5;)-kinases reactions. This method was possible by the ability of polyacrylamide gel electrophoresis (PAGE) to resolve highly phosphorylated inositol polyphosphates(20). Following IP(6;)K1 and PP-IP(5;)K enzymatic reactions using IP(6;) as the substrate, PAGE was used to separate the generated inositol pyrophosphates that were subsequently eluted in water.

Identification of an evolutionarily conserved family of inorganic polyphosphate endopolyphosphatases

Inorganic polyphosphate (poly-P) consists of just a chain of phosphate groups linked by high energy bonds. It is found in every organism and is implicated in a wide variety of cellular processes (e.g. phosphate storage, blood coagulation, and pathogenicity). Its metabolism has been studied mainly in bacteria while remaining largely uncharacterized in eukaryotes. It has recently been suggested that poly-P metabolism is connected to that of highly phosphorylated inositol species (inositol pyrophosphates). Inositol pyrophosphates are molecules in which phosphate groups outnumber carbon atoms. Like poly-P they contain high energy bonds and play important roles in cell signaling. Here, we show that budding yeast mutants unable to produce inositol pyrophosphates have undetectable levels of poly-P. Our results suggest a prominent metabolic parallel between these two highly phosphorylated molecules. More importantly, we demonstrate that DDP1, encoding diadenosine and diphosphoinositol phosphohydrolase, possesses a robust poly-P endopolyphosphohydrolase activity. In addition, we prove that this is an evolutionarily conserved feature because mammalian Nudix hydrolase family members, the three Ddp1 homologues in human cells (DIPP1, DIPP2, and DIPP3), are also capable of degrading poly-P.

The signaling role of inositol hexakisphosphate kinases (IP6Ks)

The past ten years have seen a contained explosion of interest in inositol pyrophosphates. The early cloning of the IP6Ks and the more recent identification of the PP-IP5Ks have allowed the development of essential experimental tools to investigate the physiological role of inositol pyrophosphates. However, for this exciting field of research to gain momentum, simpler and more reliable research protocols need to be further developed. The ability to resolve and quantify inositol pyrophosphates using gel electrophoresis (Losito et al., 2009) has dramatically altered the way we are studying this class of molecules, opening new avenues for research. The use of this technology to resolve, detect and characterize inositol pyrophosphates extracted from cells certainly represents one desirable aim. The most crucial objective, however, is to obtain definite proof of the new mechanism of post-translational modification by identifying with biophysical methods the presence in vivo of pyrophosphorylated serines. This will hopefully precipitate the development of new ways to detect this modification, for example through the production of antibodies that specifically recognize pyrophosphorylated serines.