Definition of Virological Endpoints Improving the Design of Human Immunodeficiency Virus (HIV) Cure Strategies Using Analytical Antiretroviral Treatment Interruption.

BACKGROUND: Analytical treatment interruption (ATI) is the gold standard in HIV research for assessing the capability of new therapeutic strategies to control viremia without antiretroviral treatment (ART). The viral setpoint is commonly used as endpoint to evaluate their efficacy. However, in line with recommendations from a consensus meeting, to minimize the risk of increased viremia without ART, trials often implement short ATI phases and stringent virological ART restart criteria. This approach can limit the accurate observation of the setpoint. METHODS: We analyzed viral dynamics in 235 people with HIV from 3 trials, examining virological criteria during ATI phases. Time-related (eg time to rebound, peak, and setpoint) and viral load magnitude-related criteria (peak, setpoint, and time-averaged AUC [nAUC]) were described. Spearman correlations were analyzed to identify (1) surrogate endpoints for setpoint and (2) optimal virological ART restart criteria mitigating the risks of ART interruption and the evaluation of viral control. RESULTS: Comparison of virological criteria between trials showed strong dependencies on ATI design. Similar correlations were found across trials, with nAUC the most strongly correlated with the setpoint, with correlations >0.70. A threshold >100 000 copies/mL for 2 consecutive measures is requested as a virological ART restart criterion. CONCLUSIONS: Our results are in line with recommendations and emphasize the benefits of an ATI phase >12 weeks, with regular monitoring, and a virological ART restart criterion of 10 000 copies/mL to limit the risk for patients while capturing enough information to keep nAUC as an optimal proxy to the setpoint.

First evidence of AXL expression on circulating tumor cells in metastatic breast cancer patients: A proof-of-concept study.

BACKGROUND: For several years, the AXL tyrosine kinase receptor, a member of the Tyro3-Axl-Mer (TAM) family, has been considered a new strategic target in oncology. AXL overexpression is common in solid tumors and is associated with poor prognosis. In this context, the detection of a subset of circulating tumor cells (CTCs) that express AXL (AXL+ CTCs) could be clinically relevant. METHODS: Immunostaining was performed to assess AXL expression in human breast cancer cell lines. The optimal conditions were established using flow cytometry. Spiking experiments were carried out to optimize the parameters of the CellSearch® system detection test. CTC enumeration and AXL expression were evaluated in patients with metastatic breast cancer (mBC) before treatment initiation. RESULTS: An innovative AXL+ CTC detection assay to be used with the CellSearch® system was developed. In a prospective longitudinal clinical trial, blood samples from 60 patients with untreated mBC were analyzed to detect AXL+ CTCs with this new assay. CTCs were detected in 35/60 patients (58.3%) and AXL+ CTCs were identified in 7 of these 35 patients (11.7% of all patients). CONCLUSION: This newly established AXL+ CTC assay is a promising tool that can be used for liquid biopsy in future clinical trials to stratify and monitor patients with cancer receiving anti-AXL therapies.

Prediction of long-term humoral response induced by the two-dose heterologous Ad26.ZEBOV, MVA-BN-Filo vaccine against Ebola.

The persistence of the long-term immune response induced by the heterologous Ad26.ZEBOV, MVA-BN-Filo two-dose vaccination regimen against Ebola has been investigated in several clinical trials. Longitudinal data on IgG-binding antibody concentrations were analyzed from 487 participants enrolled in six Phase I and Phase II clinical trials conducted by the EBOVAC1 and EBOVAC2 consortia. A model based on ordinary differential equations describing the dynamics of antibodies and short- and long-lived antibody-secreting cells (ASCs) was used to model the humoral response from 7 days after the second vaccination to a follow-up period of 2 years. Using a population-based approach, we first assessed the robustness of the model, which was originally estimated based on Phase I data, against all data. Then we assessed the longevity of the humoral response and identified factors that influence these dynamics. We estimated a half-life of the long-lived ASC of at least 15 years and found an influence of geographic region, sex, and age on the humoral response dynamics, with longer antibody persistence in Europeans and women and higher production of antibodies in younger participants.

Atezolizumab and paclitaxel as first line therapy in advanced triple-negative breast cancer patients included in the French early access program.

Following the results of the IMpassion130 trial, an early access program (EAP) was opened in France, allowing patients with PD-L1-positive advanced triple negative breast cancer (aTNBC) to receive a combination of paclitaxel and atezolizumab as first line therapy. This EAP was later discontinued when the IMpassion131 trial read out with negative results. We performed a retrospective multicentric analysis in patients who were prospectively enrolled in the French EAP. Efficacy and toxicity data were obtained on 64 patients treated from August 2019 to August 2020 in 10 French cancer centers. Median progression-free survival (PFS) and overall survival (OS) were 4.1 months (95% CI [3.0-5.8]) and 17.9 months (95% CI [12.4-NR]), respectively. The 6-months PFS rate was 28% (95% CI [16-40%]) (N = 18/64), while N = 33/64 patients (52%, 95% CI [38-63%]) experienced a tumor response. Exploratory subgroup analyses retrieved that corticosteroid use at inclusion in the EAP, before treatment initiation, was the only independent unfavorable prognostic factor for PFS (HR 2.7, 95% CI [1.3-5.6]). No new safety signal was observed. This real-life study, unique by its setting (EAP granted by anticipation and later withdrawn), suggests atezolizumab and paclitaxel has a limited efficacy in PD-L1-positive aTNBC, especially in patients receiving corticosteroids as comedication before treatment start.

Impact of variants of concern on SARS-CoV-2 viral dynamics in non-human primates.

The impact of variants of concern (VoC) on SARS-CoV-2 viral dynamics remains poorly understood and essentially relies on observational studies subject to various sorts of biases. In contrast, experimental models of infection constitute a powerful model to perform controlled comparisons of the viral dynamics observed with VoC and better quantify how VoC escape from the immune response. Here we used molecular and infectious viral load of 78 cynomolgus macaques to characterize in detail the effects of VoC on viral dynamics. We first developed a mathematical model that recapitulate the observed dynamics, and we found that the best model describing the data assumed a rapid antigen-dependent stimulation of the immune response leading to a rapid reduction of viral infectivity. When compared with the historical variant, all VoC except beta were associated with an escape from this immune response, and this effect was particularly sensitive for delta and omicron variant (p<10-6 for both). Interestingly, delta variant was associated with a 1.8-fold increased viral production rate (p = 0.046), while conversely omicron variant was associated with a 14-fold reduction in viral production rate (p<10-6). During a natural infection, our models predict that delta variant is associated with a higher peak viral RNA than omicron variant (7.6 log10 copies/mL 95% CI 6.8-8 for delta; 5.6 log10 copies/mL 95% CI 4.8-6.3 for omicron) while having similar peak infectious titers (3.7 log10 PFU/mL 95% CI 2.4-4.6 for delta; 2.8 log10 PFU/mL 95% CI 1.9-3.8 for omicron). These results provide a detailed picture of the effects of VoC on total and infectious viral load and may help understand some differences observed in the patterns of viral transmission of these viruses.

[Therapeutic advances in HER2+ breast cancer]. / Avancées thérapeutiques dans le cancer du sein HER2.

THERAPEUTIC ADVANCES IN HER2+ BREAST CANCER. 58,000 new cases of breast cancer occured in France in 2018, of which 15-20% are HER2-positive. HER2-targeted therapies deeply modified the management of these tumors, first by the introduction of monoclonal antibodies such as trastuzumab and pertuzumab and tyrosine kinase inhibitors such as tucatinib, and more recently by antibody drug conjugates (ADC), with trastuzumab-deruxtecan in the forefront. In the localized stage, neoadjuvant chemotherapy associated with trastuzumab is now the standard strategy, allowing the adjuvant strategy to be adapted to the therapeutic response, with the use of another ADC, T-DM1, in the absence of pathological complete response. These various therapeutic advances have led to a significant improvement in the prognosis of HER2-positive breast cancer, whether at the metastatic or localized stage.

AVANCÉES THÉRAPEUTIQUES DANS LE CANCER DU SEIN HER2+. Le cancer du sein représente 58 000 nouveaux cas en France en 2018, dont 15 à 20 % présentent une surexpression de HER2. Les traitements ciblant HER2 ont modifié la prise en charge des patientes : tout d'abord grâce aux anticorps tels le trastuzumab et le pertuzumab ainsi qu'aux inhibiteurs de tyrosine kinase comme le tucatinib, puis plus récemment aux anticorps conjugués, avec au premier plan le trastuzumab déruxtécan. Au stade localisé, la stratégie de chimiothérapie néoadjuvante associée au trastuzumab devient la règle, permettant d'adapter la stratégie adjuvante à la réponse au traitement, avec utilisation d'un autre anticorps conjugué, le T-DM1, en l'absence de réponse complète histologique. Ces différentes avancées ont permis une nette amélioration du pronostic du cancer du sein HER2 surexprimé, que ce soit au stade métastatique ou localisé.

Comparative validity between the Canadian and the Dutch norms of the Alberta Infant Motor Scale in a preterm population.

BACKGROUND: Prematurity remains a leading cause of motor developmental delays. The Alberta Infant Motor Scales (AIMS) is a useful tool to easily assess motor development. However, during the last decade, cross-cultural differences have been identified regarding the original AIMS norms. Therefore, the aim of this study is twofold: confirm the validity of the AIMS in a preterm population and compare the new Dutch AIMS norms to the original Canadian ones in our Belgian population. METHOD: Ninety-six preterm infants were assessed simultaneously on the AIMS and on the Bayley Scales of Infant-Toddler Development (Bayley-III) at age 9-14 months. Concurrent validity was evaluated by correlation analysis. Among these, 89 were assessed on the AIMS at age 3-6 months. Clinimetric properties of both AIMS norms were calculated to compare their ability to detect a motor delay on the Bayley-III at age 9-14 months. RESULT: Pearson's coefficient showed an excellent level of correlation between the two scales (r = 0.91). At age 3-6 months, only the 10th Canadian centile showed acceptable properties to predict a significant motor delay. At age 9-14 months, the 5th centile of both norms showed good properties to diagnose a significant motor delay, while only the Canadian norms seems to be sensitive enough to diagnose a mild motor delay. CONCLUSION: The new Dutch norms seem to be less sensitive but more specific than the Canadian ones and therefore require adapted cut-offs to diagnose motor developmental delays in a preterm population.

Modelling the response to vaccine in non-human primates to define SARS-CoV-2 mechanistic correlates of protection.

The definition of correlates of protection is critical for the development of next-generation SARS-CoV-2 vaccine platforms. Here, we propose a model-based approach for identifying mechanistic correlates of protection based on mathematical modelling of viral dynamics and data mining of immunological markers. The application to three different studies in non-human primates evaluating SARS-CoV-2 vaccines based on CD40-targeting, two-component spike nanoparticle and mRNA 1273 identifies and quantifies two main mechanisms that are a decrease of rate of cell infection and an increase in clearance of infected cells. Inhibition of RBD binding to ACE2 appears to be a robust mechanistic correlate of protection across the three vaccine platforms although not capturing the whole biological vaccine effect. The model shows that RBD/ACE2 binding inhibition represents a strong mechanism of protection which required significant reduction in blocking potency to effectively compromise the control of viral replication.

Pharmacokinetic Variability Drives Palbociclib-Induced Neutropenia in Metastatic Breast Cancer Patients: Drug-Drug Interactions Are the Usual Suspects.

Palbociclib is a good candidate for therapeutic drug monitoring (TDM) due to its narrow therapeutic range and frequency of toxicities, particularly high-grade neutropenia. In this prospective, bicentric clinical trial, we evaluated the palbociclib exposure−toxicity relationship and determined the relevant sources of palbociclib pharmacokinetic variability, including drug−drug interactions (DDI). We followed 58 patients (mean age: 62.9 years) for 1 year. The geometric median of palbociclib plasma trough concentration (Ctrough) was 74.1 ng/mL. Neutropenia occurred in 70.7% of patients (high grade in 67.2% of patients). High-grade neutropenia occurrence during the first two palbociclib cycles was higher in patients with lower neutrophil count at initiation (p = 0.002). Palbociclib plasma Ctrough was correlated with high-grade neutropenia occurrence during the first two cycles (p = 0.024, OR 5.51). Co-treatment with agents that may interfere with palbociclib PK significantly influenced palbociclib Ctrough (p < 0.05). CYP3A4/P-glycoprotein inhibitors increased by 25% palbociclib Ctrough (p = 0.035), while antacids reduced it by 20% (p = 0.036). However, DDI did not have any significant effect on high-grade neutropenia occurrence (p > 0.05). This study confirms the major role of TDM to manage palbociclib safe use from the first week of treatment, particularly the significant incidence of hematological toxicity. Moreover, this first dedicated prospective study confirmed the importance of characterizing co-treatments to limit the DDI risk with oral-targeted therapies.

Progression-free survival on endocrine therapy, before or after chemotherapy, in hormone receptor-positive HER2-negative metastatic breast cancer.

PURPOSE: A major question when treating HR+/HER2- metastatic breast cancer (MBC) is whether early introduction of chemotherapy (CT) increases endocrine resistance. We aimed to describe progression-free survival (PFS) under first endocrine therapy (ET) depending on whether given before or after CT in a large nationwide cohort, in the pre-CDK era. METHODS: The real-life retrospective ESME database includes all patients with MBC whose first-line treatment was initiated between 2008 and 2014 in one of the 18 French Comprehensive Cancer Centres. Our primary objective was to compare PFS from start of first ET in patients with HR+/HER2- MBC who received ET or CT first. RESULTS: We identified 6293 patients who received at least one ET line during their first two therapeutic lines for MBC. As first-line therapy, 3832 (60.9%) received ET alone (ET1 1st group), whilst 2461 (39.1%) received CT, including 2024 patients (32.2%) with maintenance ET after CT (ET1 after CT group). Median PFS under first ET was 12.4 months (95% CI 11.9-13.1) in ET 1st group vs. 12.6 months in ET1 after CT group (95% CI 12.1-13.4), HR 0.96 (95% CI 0.90-1.01, P = 0.1277). CONCLUSIONS: PFS under first ET appears identical whether prescribed before or after chemotherapy. These data suggest chemotherapy does not promote endocrine resistance.

Impact of pharmacist consultation at clinical trial inclusion: an effective way to reduce drug-drug interactions with oral targeted therapy.

PURPOSE: Pharmacist consultation is unfrequently performed in oncology clinical trials that include patients who often have many co-treatments increasing the risk of drug-drug interactions (DDI). The aim of this study was to determine whether best possible medication history (BPMH) by hospital pharmacist at inclusion and therapeutic drug monitoring could be used for DDI risk evaluation and for current oral targeted therapy management. METHODS: A prospective clinical trial (ALCINA 2, NCT04025541) was carried out in metastatic breast cancer cohort treated by palbociclib to conduct pharmacokinetics-toxicity correlation study. BPMH was prospectively performed by the hospital pharmacist at each trial inclusion, followed by a contact to the patient's community pharmacy to complete the collected data. Pharmacokinetic analysis was performed on blood samples collected at day 15 of cycle 1 of palbociclib treatment. RESULTS: Pharmacist interventions indicated that at inclusion, current medications were incomplete for 63% of the enrolled patients (32/51). It allowed the real-time management of high-risk DDI detected in third of patients. The palbociclib Ctrough geometric median (min-max) was significantly higher in cohort with potential DDI [106 ng/mL (66.7-113)], than cohort without potential DDI [70.1 ng/mL (54.1-89.7)], p = 0.0284. CONCLUSION: This is the first prospective study evaluating the relevance of proactive BPMH by pharmacist with contact to the community pharmacy during the inclusion step of a clinical trial to ensure the efficacy and safety of the investigated drug. This investigation was thus able to highlight the statistically significant impact of these DDI on palbociclib plasma concentration variation during the clinical trial. TRIAL REGISTRATION: Clinicaltrials.gov identifier NCT04025541.

Between-group comparison of area under the curve in clinical trials with censored follow-up: Application to HIV therapeutic vaccines.

In clinical trials, longitudinal data are commonly analyzed and compared between groups using a single summary statistic such as area under the outcome versus time curve (AUC). However, incomplete data, arising from censoring due to a limit of detection or missing data, can bias these analyses. In this article, we present a statistical test based on splines-based mixed-model accounting for both the censoring and missingness mechanisms in the AUC estimation. Inferential properties of the proposed method were evaluated and compared to ad hoc approaches and to a non-parametric method through a simulation study based on two-armed trial where trajectories and the proportion of missing data were varied. Simulation results highlight that our approach has significant advantages over the other methods. A real working example from two HIV therapeutic vaccine trials is presented to illustrate the applicability of our approach.

Alpelisib for the treatment of PIK3CA-mutated, hormone receptor-positive, HER2-negative metastatic breast cancer.

Introduction: Two-thirds of advanced breast cancers are hormone receptor (HR)-positive and human epidermal growth factor receptor 2 (HER2)-negative (HR+/HER2-). Gene mutations in PIK3CA, encoding the PI3K catalytic subunit alpha of phosphatidyl-inositol 3-kinase (PI3K), are a frequent event in this population and are implicated in hormone therapy resistance. Alpelisib is a PI3K-alpha inhibitor and is the first PI3K inhibitor approved, in association with fulvestrant, by the FDA and EMA, based on improved progression-free survival (PFS) versus fulvestrant alone in a randomized phase III trial in HR+/HER2-, PIK3CA-mutated tumors following progression on/after HT.Areas covered: The scientific rationale, preclinical development, pharmacokinetics, and clinical efficacy/safety of alpelisib-fulvestrant are summarized. The role of alpelisib in the clinical setting is discussed, referencing current therapeutic options and clinical challenges associated with alpelisib's safety profile.Expert opinion: Alpelisib is an option for patients with HR+/HER2-, PIK3CA-mutated tumors whose disease progressed during/after aromatase inhibitor treatment. The PFS benefit appears clinically significant over fulvestrant alone, with a 7.9 months, non-significant, improvement in overall survival. Its safety profile requires strict patient selection, mainly based on baseline glycemic status, and close monitoring.

Liquid chromatography-tandem mass spectrometric assay for the quantification of CDK4/6 inhibitors in human plasma in a clinical context of drug-drug interaction.

The CDK4/6 inhibitors palbociclib and ribociclib are kinase inhibitors used in association with hormonal therapy for the management of patients with metastatic breast cancer. Like most kinase inhibitors, therapeutic drug monitoring may be used for personalize their dosage. To this aim, we developed and validated a sensitive and specific HPLC-MS/MS method for palbociclib and ribociclib quantification in blood samples. We then quantified exposure to palbociclib (plasma trough concentration; Ctrough) in a real-life cohort of patients with locally invasive or metastatic breast cancer (n = 18) at day 15 of the first cycle of palbociclib treatment to characterize palbociclib concentration at steady state (Clinicaltrials.gov identifier NCT04025541, IdRCB n° 2018-A00064-51, 03/07/2018). The geometric mean (± standard deviation [min-max]) of palbociclib plasma Ctrough was 88.58 ng/mL (± 26.4 [46.5 ng/mL - 133 ng/mL]) at day 15. Some covariates, such as drug-drug interactions, could explain the concentration variations observed in our Caucasian cohort. These first results in real-life settings obtained with our HPLC-MS/MS method give important information on palbociclib monitoring and pharmacokinetic variability.

Decision of Adjuvant Systemic Treatment in HR+ HER2- Early Invasive Breast Cancer: Which Biomarkers Could Help?

The decision to administer adjuvant chemotherapy in treatment of early invasive breast cancer (EBC) is often complex, particularly for hormone receptor-positive (HR+) diseases, and current guidelines often classify these patients in an intermediate-risk group. Several biomarkers are currently available in this indication, in order to obtain additional and more accurate prognostic information compared to classic clinicopathological characteristics and guide the indication of adjuvant chemotherapy, optimizing the efficacy/toxicity ratio. We conducted a systematic review to evaluate the clinical validity and clinical utility of five biomarkers (uPA/PAI-1, OncotypeDX®, MammaPrint®, PAM50, and EndoPredict®) in HR+/HER2- EBC, whatever the nodal status. A total of 89 studies met the inclusion criteria. Even though data currently available confirm the clinical validity of these biomarkers, there is a lack of data regarding clinical utility for most of them. Prospective studies in well-defined populations are needed to integrate these biomarkers in a decision strategy.

Strategies for clinical development of monoclonal antibodies beyond first-in-human trials: tested doses and rationale for dose selection.

BACKGROUND: Our previous survey on first-in-human trials (FIHT) of monoclonal antibodies (mAbs) showed that, due to their limited toxicity, the recommended phase II dose (RP2D) was only tentatively defined. METHODS: We identified, by MEDLINE search, articles on single-agent trials of mAbs with an FIHT included in our previous survey. For each mAb, we examined tested dose(s) and dose selection rationale in non-FIHTs (NFIHTs). We also assessed the correlation between doses tested in the registration trials (RTs) of all FDA-approved mAbs and the corresponding FIHT results. RESULTS: In the 37 dose-escalation NFIHTs, the RP2D indication was still poorly defined. In phase II-III NFIHTs (n=103 on 37 mAbs), the FIHT RP2D was the only dose tested for five mAbs. For 16 mAbs, only doses different from the FIHT RP2D or the maximum administered dose (MAD) were tested and the dose selection rationale infrequently indicated. In the 60 RTs on 27 FDA-approved mAbs with available FIHT, the FIHT RP2D was tested only for two mAbs, and RT doses were much lower than the FIHT MAD. CONCLUSIONS: The rationale beyond dose selection in phase II and III trials of mAbs is often unclear in published articles and not based on FIHT data.

Prognostic impact of the inclusion of uPA/PAI-1 for adjuvant treatment decision-making in ER+/Her2- pN0 early breast cancers.

PURPOSE: Intermediate-risk early breast cancer (EBC) is a heterogeneous group in which adjuvant chemotherapy decision proves to be difficult. Clinical and pathological criteria are sometimes insufficient to determine the best therapeutic options, and validated biomarkers such as uPA/PAI-1, are needed to contribute to the decision-making. The objective of this study was to evaluate the clinical outcome of an unselected ER+/HER2- pN0 EBC cohort of patients in whom the routine clinical decision process included a prospective uPA/PAI-1 determination. METHOD: This monocentric retrospective study included 520 patients who underwent curative surgery in our institute between 2006 and 2011. Adjuvant therapeutic strategy was decided based on clinical-pathological data, altogether with a routine prospective determination of uPA/PAI-1 tumor levels using fresh, extemporaneously sampled tissue. We evaluated the correlation between uPA/PAI-1 levels, clinical-pathological variables, and the patient's outcome (relapse-free survival, RFS, and overall survival, OS). RESULT: Median follow-up was 5.4 years. The 5- and 10-year RFS rates were ,respectively, 95 and 89%, and the five-year OS rate was 96.3%. Forty percent of tumors had low uPA/PAI-1 levels. Seventy-five percent of patients with low uPA/PAI-1 levels did not receive chemotherapy, when 25% did. Sixty percent of patients with high uPA and/or PAI-1 levels received chemotherapy, while 40% did not. No statistical significant correlation was found between the uPA/PAI-1 levels and RFS or OS. CONCLUSION: The personalization of the patients' treatment using uPA/PAI-1 tumor levels allows the reversion of the well-known poor prognostic impact of high uPA/PAI-1 levels and strongly supports the use of this biomarker in clinical practice.

Clinical Development Strategies and Outcomes in First-in-Human Trials of Monoclonal Antibodies.

PURPOSE: We conducted a comprehensive review of the design, implementation, and outcome of first-in-human (FIH) trials of monoclonal antibodies (mAbs) to clearly determine early clinical development strategies for this class of compounds. METHODS: We performed a PubMed search using appropriate terms to identify reports of FIH trials of mAbs published in peer-reviewed journals between January 2000 and April 2013. RESULTS: A total of 82 publications describing FIH trials were selected for analysis. Only 27 articles (33%) reported the criteria used for selecting the starting dose (SD). Dose escalation was performed using rule-based methods in 66 trials (80%). The median number of planned dose levels was five (range, two to 13). The median of the ratio between the highest planned dose and the SD was 27 (range, two to 3,333). Although in 56 studies (68%) at least one grade 3 or 4 toxicity event was reported, no dose-limiting toxicity was observed in 47 trials (57%). The highest planned dose was reached in all trials, but the maximum-tolerated dose (MTD) was defined in only 13 studies (16%). The median of the ratio between MTD and SD was eight (range, four to 1,000). The recommended phase II dose was indicated in 34 studies (41%), but in 25 (73%) of these trials, this dose was chosen without considering toxicity as the main selection criterion. CONCLUSION: This literature review highlights the broad design heterogeneity of FIH trials testing mAbs. Because of the limited observed toxicity, the MTD was infrequently reached, and therefore, the recommended phase II dose for subsequent clinical trials was only tentatively defined.