MAIP: An Open-Source Tool to Enrich High-Throughput Screening Output and Identify Novel, Druglike Molecules with Antimalarial Activity.

Efforts to tackle malaria must continue for a disease that threatens half of the global population. Parasite resistance to current therapies requires new chemotypes that are able to demonstrate effectiveness and safety. Previously, we developed a machine-learning-based approach to predict compound antimalarial activity, which was trained on the compound collections of several organizations. The resulting prediction platform, MAIP, was made freely available to the scientific community and offers a solution to prioritize molecules of interest in virtual screening and hit-to-lead optimization. Here, we experimentally validate MAIP and demonstrate how the approach was used in combination with a robust compound selection workflow and a recently introduced innovative high-throughput screening (HTS) cascade to select and purchase compounds from a public library for subsequent experimental screening. We observed a 12-fold enrichment compared with a randomly selected set of molecules, and the eight hits we ultimately selected exhibit good potency and absorption, distribution, metabolism, and excretion (ADME) profiles.

Biweekly vs Triweekly Cabazitaxel in Older Patients With Metastatic Castration-Resistant Prostate Cancer: The CABASTY Phase 3 Randomized Clinical Trial.

Importance: Many patients 65 years or older with metastatic castration-resistant prostate cancer (mCRPC) are denied taxane chemotherapy because this treatment is considered unsuitable. Objective: To determine whether biweekly cabazitaxel (CBZ), 16 mg/m2 (biweekly CBZ16), plus prophylactic granulocyte colony-stimulating factor (G-CSF) at each cycle reduces the risk of grade 3 or higher neutropenia and/or neutropenic complications (eg, febrile neutropenia, neutropenic infection, or sepsis) compared with triweekly CBZ, 25 mg/m2 (triweekly CBZ25), plus G-CSF (standard regimen). Design, Setting, and Participants: A total of 196 patients 65 years or older with progressive mCRPC were enrolled in this prospective phase 3 randomized clinical trial conducted in France (18 centers) and Germany (7 centers) between May 5, 2017, and January 7, 2021. All patients had received docetaxel and at least 1 novel androgen receptor-targeted agent. Interventions: Patients were randomly assigned 1:1 to receive biweekly CBZ16 plus G-CSF and daily prednisolone (experimental group) or triweekly CBZ25 plus G-CSF and daily prednisolone (control group). Main Outcome and Measures: The primary end point was the occurrence of grade 3 or higher neutropenia measured at nadir and/or neutropenic complications. Results: Among 196 patients (97 in the triweekly CBZ25 group and 99 in the biweekly CBZ16 group), the median (IQR) age was 74.6 (70.4-79.3) years, and 181 (92.3%) had an Eastern Cooperative Oncology Group performance status of 0 or 1. The median (IQR) follow-up duration was 31.3 (22.5-37.5) months. Relative dose intensities were comparable between groups (median [IQR], 92.7% [83.7%-98.9%] in the triweekly CBZ25 group vs 92.8% [87.0%-98.9%] in the biweekly CBZ16 group). The rate of grade 3 or higher neutropenia and/or neutropenic complications was significantly higher with triweekly CBZ25 vs biweekly CBZ16 (60 of 96 [62.5%] vs 5 of 98 [5.1%]; odds ratio, 0.03; 95% CI, 0.01-0.08; P < .001). Grade 3 or higher adverse events were more common with triweekly CBZ25 (70 of 96 [72.9%]) vs biweekly CBZ16 (55 of 98 [56.1%]). One patient (triweekly CBZ25 group) died of a neutropenic complication. Conclusions and Relevance: In this randomized clinical trial, compared with the standard regimen, biweekly CBZ16 plus G-CSF significantly reduced by 12-fold the occurrence of grade 3 or higher neutropenia and/or neutropenic complications, with comparable clinical outcomes. The findings suggest that biweekly CBZ16 regimen should be offered to patients 65 years or older with mCRPC for whom the standard regimen is unsuitable. Trial Registration: ClinicalTrials.gov Identifier: NCT02961257.

The Parasite Reduction Ratio (PRR) Assay Version 2: Standardized Assessment of Plasmodium falciparum Viability after Antimalarial Treatment In Vitro.

With artemisinin-resistant Plasmodium falciparum parasites emerging in Africa, the need for new antimalarial chemotypes is persistently high. The ideal pharmacodynamic parameters of a candidate drug are a rapid onset of action and a fast rate of parasite killing or clearance. To determine these parameters, it is essential to discriminate viable from nonviable parasites, which is complicated by the fact that viable parasites can be metabolically inactive, whilst dying parasites can still be metabolically active and morphologically unaffected. Standard growth inhibition assays, read out via microscopy or [3H] hypoxanthine incorporation, cannot reliably discriminate between viable and nonviable parasites. Conversely, the in vitro parasite reduction ratio (PRR) assay is able to measure viable parasites with high sensitivity. It provides valuable pharmacodynamic parameters, such as PRR, 99.9% parasite clearance time (PCT99.9%) and lag phase. Here we report the development of the PRR assay version 2 (V2), which comes with a shorter assay duration, optimized quality controls and an objective, automated analysis pipeline that systematically estimates PRR, PCT99.9% and lag time and returns meaningful secondary parameters such as the maximal killing rate of a drug (Emax) at the assayed concentration. These parameters can be fed directly into pharmacokinetic/pharmacodynamic models, hence aiding and standardizing lead selection, optimization, and dose prediction.

The Pandemic Response Box─Accelerating Drug Discovery Efforts after Disease Outbreaks.

The current Covid-19 pandemic has underlined the need for a more coordinated and forward-looking investment in the search for new medicines targeting emerging health care threats. Repositioning currently approved drugs is a popular approach to any new emerging disease, but it represents a first wave of response. Behind this would be a second wave of more specifically designed therapies based on activities against specific molecular targets or in phenotypic assays. Following the successful deployment and uptake of previous open access compound collections, we assembled the Pandemic Response Box, a collection of 400 compounds to facilitate drug discovery in emerging infectious disease. These are based on public domain information on chemotypes currently in discovery and early development which have been shown to have useful activities and were prioritized by medicinal chemistry experts. They are freely available to the community as a pharmacological test set with the understanding that data will be shared rapidly in the public domain.

TAXOMET: A French Prospective Multicentric Randomized Phase II Study of Docetaxel Plus Metformin Versus Docetaxel Plus Placebo in Metastatic Castration-Resistant Prostate Cancer.

BACKGROUND: Docetaxel (DOCE) is a standard of care in metastatic castration-resistant prostate cancer (mCRPC). Several retrospective studies suggested a decrease in Prostate Cancer incidence and mortality with metformin (MET). MET has also demonstrated anti-tumor activity in Prostate Cancer preclinical models, with increased apoptosis when added to DOCE. We aimed at exploring the role of MET in combination with DOCE in mCRPC. PATIENTS AND METHODS: Non-diabetic mCRPC patients were randomly assigned to receive DOCE 75 mg/m2 every 21 days + prednisone (5 mg. BID) with either MET 850 mg BID (D+M) or placebo (D+P) up to 10 cycles. Prostate-Specific Antigen (PSA) response ≥50% from baseline was the primary end point. Secondary end points included objective response rate (ORR), progression-free survival (PFS), overall survival (OS), toxicity and quality of life (QoL). RESULTS: Out of 99 patients were randomized (D+M = 50; D+P = 49) in 10 French centers. The median follow-up was 86 (IQR 73-88) months. The PSA-response rate reached 66% in the D+M arm, but was not different from that observed in the D+P arm (63%, P = 0,94). In the D+M and D+P arms, the ORR was 28% and 24%, the median PFS was 7.8 and 6.0 months and the median OS was 27 and 20 months (ns), respectively. Diarrhea grade I to II was more frequent in the MET arm (66% vs. 43%). No impairment of QoL was observed. CONCLUSION: MET addition failed to improve the standard DOCE regimen in mCRPC. Further research targeting tumor cell metabolism should be performed.

Efficacy and safety of panitumumab in a cohort of patients with metastatic colorectal cancer in France: PANI OUEST, a post-EMA-approval descriptive study with a geriatric oncology focus.

BACKGROUND/AIMS: The Bretagne-Pays de la Loire cancer observatory, an oncology network created by the French Ministry of Health, is specifically dedicated to assess the use of new targeted anticancer therapies in routine practice. In line with the French National Cancer III program, our cancer network set up a real-life cohort, which is independent of the pharmaceutical industry, for patients with colorectal cancer to monitor patient safety and quality of care and promote pharmacovigilance. MATERIALS AND METHODS: Panitumumab monotherapy was assessed in 243 patients with wild-type Kirsten rat sarcoma who were treated for metastatic colorectal cancer (mCRC) between July 2008 and December 2010 after prior chemotherapy using oxaliplatine and irinotecan. This was a post-European medicine agency marketing (EMA-M) study Results: This study shed light on the best practices, strategic adaptations, clinical results (treatment objective responses, 13%; progression free survival, 2.99 months [2.73-3.15]; and overall survival, 6.8 months [5.49-8.38]) as well as expected or unexpected (grade 3 or 4: 11.5%) secondary effects in the phase IV panitumumab treatment of mCRC. CONCLUSION: Our results are similar to those by Amado whose phase III study led to obtaining EMA-M for panitumumab and tend to confirm the antitumor activity of this antiepidermal growth factor receptor antibody in the treatment of mCRC. In addition, our results opened avenues to further assessment of panitumumab use as monotherapy as well as its benefit-risk ratio while taking into account the patients' general and clinical characteristics. In 2012, the French National Authority for Health appended these data to the panitumumab transparency committee report.

Identification and optimization of an aminoalcohol-carbazole series with antimalarial properties.

Recent observations on the emergence of artemisinin resistant parasites have highlighted the need for new antimalarial treatments. An HTS campaign led to the identification of the 1-(1-aminopropan-2-ol)carbazole analogues as potent hits against Plasmodium falciparum K1 strain. The SAR study and optimization of early ADME and physicochemical properties direct us to the selection of a late lead compound that shows good efficacy when orally administrated in the in vivo P. berghei mouse model.

Analysis of pan-African Centres of excellence in health innovation highlights opportunities and challenges for local innovation and financing in the continent.

A pool of 38 pan-African Centres of Excellence (CoEs) in health innovation has been selected and recognized by the African Network for Drugs and Diagnostics Innovation (ANDI), through a competitive criteria based process. The process identified a number of opportunities and challenges for health R&D and innovation in the continent: i) it provides a direct evidence for the existence of innovation capability that can be leveraged to fill specific gaps in the continent; ii) it revealed a research and financing pattern that is largely fragmented and uncoordinated, and iii) it highlights the most frequent funders of health research in the continent. The CoEs are envisioned as an innovative network of public and private institutions with a critical mass of expertise and resources to support projects and a variety of activities for capacity building and scientific exchange, including hosting fellows, trainees, scientists on sabbaticals and exchange with other African and non-African institutions.

Integrated dataset of screening hits against multiple neglected disease pathogens.

New chemical entities are desperately needed that overcome the limitations of existing drugs for neglected diseases. Screening a diverse library of 10,000 drug-like compounds against 7 neglected disease pathogens resulted in an integrated dataset of 744 hits. We discuss the prioritization of these hits for each pathogen and the strong correlation observed between compounds active against more than two pathogens and mammalian cell toxicity. Our work suggests that the efficiency of early drug discovery for neglected diseases can be enhanced through a collaborative, multi-pathogen approach.

Patterns of aging in the long-lived wandering albatross.

How does an animal age in natural conditions? Given the multifaceted nature of senescence, identifying the effects of age on physiology and behavior remains challenging. We investigated the effects of age on a broad array of phenotypic traits in a wild, long-lived animal, the wandering albatross. We studied foraging behavior using satellite tracking and activity loggers in males and females (age 6-48+ years), and monitored reproductive performance and nine markers of baseline physiology known to reflect senescence in vertebrates (humoral immunity, oxidative stress, antioxidant defenses, and hormone levels). Age strongly affected foraging behavior and reproductive performance, but not baseline physiology. Consistent with results of mammal and human studies, age affected males and females differently. Overall, our findings demonstrate that age, sex, and foraging ability interact in shaping aging patterns in natural conditions. Specifically, we found an unexpected pattern of spatial segregation by age; old males foraged in remote Antarctica waters, whereas young and middle-aged males never foraged south of the Polar Front. Old males traveled a greater distance but were less active at the sea surface, and returned from sea with elevated levels of stress hormone (corticosterone), mirroring a low foraging efficiency. In contrast to findings in captive animals and short-lived birds, and consistent with disposable soma theory, we found no detectable age-related deterioration of baseline physiology in albatrosses. We propose that foraging efficiency (i.e., the ability of individuals to extract energy from their environment) might play a central role in shaping aging patterns in natural conditions.

Robust hit identification by quality assurance and multivariate data analysis of a high-content, cell-based assay.

Recent technological advances in high-content screening instrumentation have increased its ease of use and throughput, expanding the application of high-content screening to the early stages of drug discovery. However, high-content screens produce complex data sets, presenting a challenge for both extraction and interpretation of meaningful information. This shifts the high-content screening process bottleneck from the experimental to the analytical stage. In this article, the authors discuss different approaches of data analysis, using a phenotypic neurite outgrowth screen as an example. Distance measurements and hierarchical clustering methods lead to a profound understanding of different high-content screening readouts. In addition, the authors introduce a hit selection procedure based on machine learning methods and demonstrate that this method increases the hit verification rate significantly (up to a factor of 5), compared to conventional hit selection based on single readouts only.

A high-throughput mammalian protein expression, purification, aliquoting and storage pipeline to assemble a library of the human secretome.

In the post-human genome-sequencing era, the availability of recombinant proteins has become crucial for the identification of proteins with therapeutic potential. Based upon bioinformatic coding predictions of the genes for putative secreted proteins, we established a high-throughput protein pipeline (HTPP) for the production of a subset of the human secretome. The HTPP was based on a transient expression system in HEK293-EBNA cells at 100 to 500 mL culture scale, combined with an automated affinity purification procedure targeting >75% purity. This was followed by a semi-automated protein sample logistics to provide biologists with quality-controlled and 96 well formatted protein aliquots amenable to cell-based assays. Over a 4-year period, beginning in 2001, we performed over 7,500 transfections representing over 2,200 registered proteins, including both novel and reference proteins, at an average production of 280 proteins/month with a peak production of 320 proteins/month. All these proteins have been tested in more than 50 different cell-based assays. This article describes the major process steps and highlights the optimization required to maintain novel protein production while supporting both stock replenishment and scale-up productions.

A microfluidics-based mobility shift assay to discover new tyrosine phosphatase inhibitors.

Protein tyrosine phosphatases (PTPs) play key roles in regulating tyrosine phosphorylation levels in cells. Since the discovery of PTP1B as a major drug target for diabetes and obesity, PTPs have emerged as a new and promising class of signaling targets for drug development in a variety of therapeutic areas. The routine use of generic substrate 6,8-difluoro-4-methylumbelliferyl phosphate (DiFMUP) in our hands led to the discovery of very similar and often not very selective molecules. Therefore, to increase the chances to discover novel chemical scaffolds, a side-by-side comparison between the DiFMUP assay and a chip-based mobility shift assay with a specific phosphopeptide was performed, on 1 PTP, using a focused set of compounds. Assay robustness and sensitivity were comparable for both the DiFMUP and mobility shift assays. The off-chip mobility shift assay required a longer development time because of identification, synthesis, and characterization of a specific peptide, and its cost per point was higher. However, although most potent scaffolds found with the DiFMUP assay were confirmed in the mobility shift format, the off-chip mobility shift assay led to the identification of previously unidentified chemical scaffolds with improved druglike properties.