Identification of novel PI3K inhibitors through a scaffold hopping strategy.

A scaffold hopping strategy, including intellectual property availability assessment, was successfully applied for the discovery of novel PI3K inhibitors. Compounds were designed based on the chemical structure of the lead compound ETP-46321, a potent PI3K inhibitor, previously reported by our group. The new generated compounds showed good in vitro potency and selectivity, proved to inhibit potently the phosphorylation of AKTSer473 in cells and demonstrated to be orally bioavailable, thus becoming potential back-up candidates for ETP-46321.

Identification of ETP-46321, a potent and orally bioavailable PI3K α, δ inhibitor.

Phosphoinositide-3-kinase (PI3K) is an important target for cancer therapeutics due to the deregulation of this signaling pathway in a wide variety of human cancers. Herein, we describe the optimization of imidazo [1,2-a] pyrazines, which allow us to identify compound 14 (ETP-46321), with potent biochemical and cellular activity and good pharmacokinetic properties (PK) after oral dosing. ETP-46321 PK/PD studies showed time dependent downregulation of AKT(Ser473) phosphorylation, which correlates with compound levels in tumor tissue and demonstrating to be efficacious in a GEMM mouse tumor model driven by a K-Ras(G12V) oncogenic mutation. Treatment with ETP-46321 resulted in significant tumor growth inhibition.

Rapid identification of ETP-46992, orally bioavailable PI3K inhibitor, selective versus mTOR.

Phosphoinositide-3-kinases (PI3K) are a family of lipid kinases mediating numerous cell processes such as proliferation, migration and differentiation. PI3K is an important target for cancer therapeutics due to the deregulation of this signaling pathway in a wide variety of human cancers. Herein, we describe the rapid identification of ETP-46992, within 2-aminocarbonyl imidazo [1,2-a] pyrazine series, with suitable pharmacokinetic (PK) properties that allows the establishment of mechanism of action and efficacy in vivo studies. ETP-46992 showed tumor growth inhibition in a GEMM mouse tumor model driven by a K-Ras(G12V) oncogenic mutation and in tumor xenograft models with PI3K pathway deregulated (BT474).

Subcutaneous Sarilumab in hospitalised patients with moderate-severe COVID-19 infection compared to the standard of care (SARCOVID): a structured summary of a study protocol for a randomised controlled trial.

OBJECTIVES: The main aim of the study is to evaluate the efficacy of a single dose of sarilumab, in subcutaneous administration, in hospitalised patients with moderate to early severe COVID-19 infection compared to the current standard of care, to prevent progression to systemic hyperinflammatory status. Our hypothesis is that use of subcutaneous sarilumab in early stages (window of opportunity) of COVID-19 moderate-severe pneumonia can prevent higher oxygenation requirements through non-invasive and invasive mechanical ventilation and decrease in-hospital stays, as well as death rate. The secondary objectives of the study are to evaluate the safety of sarilumab through hospitalisation and up to day 14 after discharge, compared to the control arm as assessed by incidence of serious and non serious adverse events (SAEs). In addition, as an exploratory objective, to compare the baseline clinical and biological parameters, including serum IL-6 levels, of the intervention population against controls of the same pandemic outbreak (using a propensity score) to search for markers that identify the best candidates for the treatment with subcutaneous IL-6R inhibitors and to attempt an approximation in the temporal frame of the "window of opportunity" TRIAL DESIGN: SARCOVID is an investigator-initiated single center randomised proof of concept study. PARTICIPANTS: Patients treated at the Hospital Universitario La Princesa, Madrid, Spain requiring hospitalisation will be consecutively recruited, meeting all inclusion criteria and none of the exclusion criteria Inclusion criteria a. Age >18, <80 years old b. COVID-19 infection documented by a positive RT-PCR test or, in absence of a RT-PCR positive test, case definition of COVID 19 infection/pneumonia as per local protocol and the presence of a positive serologic test (IgM/IgA by ELISA) c. Documented interstitial pneumonia requiring admission and at least two of the following parameters: 1) Fever ≥ 37.8°C (tympanic) 2) IL-6 in serum ≥ 25 pg/mL (in the absence of a previous dose of prednisone or equivalent> 1 mg / kg) or PCR> 5mg/dL 3) Lymphocytes <600 cells/mm3 4) Ferritin> 300 µg/L that doubles in 24 hours 5) Ferritin> 600 µg/L in the first determination and LDH> 250 U/L 6) D-dimer (> 1 mg/L) d. Informed verbal consent or requested under urgent conditions, documented in the electronic medical record. Exclusion criteria a. Patients who require mechanical ventilation at the time of inclusion. b. AST / ALT values > 5 folds the ULN. c. Absolute neutrophil count below 500 cells/mm3 d. Absolute platelet count below 50,000 cells/mm3 e. Documented sepsis or high suspicion of superimposed infection by pathogens other than COVID-19. f. Presence of comorbidities that can likely lead to an unfavourable result according to clinical judgment. g. Complicated diverticulitis or intestinal perforation. h. Current skin infection (eg, uncontrolled dermopiodermitis). i. Immunosuppressive anti-rejection therapy. j. Pregnancy or lactation. k. Previous treatment with tocilizumab or sarilumab. l. Patients participating in another clinical trial for SARS-CoV-2 infection. m. Patients with known hypersensitivity or contraindication to sarilumab or excipients. INTERVENTION AND COMPARATOR: The intervention group, sarilumab plus standard of care, will receive 400 mg single dose treatment with Sarilumab (Kevzara), 2 subcutaneous injections 200mg each in a pre-filled syringe. Treatment with drugs or procedures in routine clinical practice that the clinician responsible for the patient deems necessary is allowed. The control group will receive drugs or procedures in routine clinical practice according to the best standard of care as per local protocol. MAIN OUTCOMES: Primary Outcome Measures 1. Mean change in clinical status assessment using the 7-point ordinal scale at day 7 after randomisation compared to baseline (Score ranges 1-7) 1. Death; 2. Hospitalised, requiring invasive mechanical ventilation or extracorporeal membrane oxygenation (ECMO); 3. Hospitalised, requiring non-invasive ventilation or high flow oxygen devices; 4. Hospitalised, requiring supplemental oxygen; 5. Hospitalised, not requiring supplemental oxygen - but in need of ongoing medical care (COVID-19 related or otherwise) 6. Hospitalised, not requiring supplemental oxygen - no longer requires ongoing medical care (independent) 7. Not hospitalised 2. Duration of hospitalisation: Days from the date of enrolment to the date of discharge 3. Number of deaths at the end of study RANDOMISATION: Randomisation to treatment arms sarilumab plus standard of care or standard of care in a 2:1 ratio will be performed by the Clinical Research and Clinical Trials Unit (CRCTU) at the Hospital using a table of random numbers, an internet-based randomisation tool. After checking that all inclusion criteria are met and none of the exclusion criteria, CRCTU will communicate the recruiting investigator the assigned treatment. BLINDING (MASKING): This study is unblinded. NUMBERS TO BE RANDOMISED (SAMPLE SIZE): 30 patients treated by COVID-19 infection who require hospitalisation: 20 will receive sarilumab plus Standard of Care and 10 will receive Standard of Care. TRIAL STATUS: The Protocol version number is 2, as of 6th April 2020, with amendment 1, as of 7th May 2020. The recruitment is ongoing. Recruitment started on April 13th 2020 and is anticipated to be completed by November 2020. TRIAL REGISTRATION: This trial was first registered in the European Union Clinical Trials Register on 4 April 2020, EudraCT Number 2020-001634-36 . Then, posted on ClinicalTrials.gov on 22 April 2020, Identifier: NCT04357808 . FULL PROTOCOL: The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol. The study protocol has been reported in accordance with the International Council Harmonization guidelines: https://www.ich.org/page/efficacy-guidelines .

Influence of (hydroxymethyl)pyridine and pyridine-carboxylic acids, in trans-position to the isopropylamine and amine ligands, on the cytotoxicity of platinum complexes.

trans-Pt(II) Complexes with aliphatic amines and planar amines such as (hydroxymethyl)pyridines, and pyridine-3- and pyridine-4-carboxylic acids were synthesized and screened for their potential cytotoxic activity in different cancer cell lines used at the NCI for in vitro screens, i.e., MCF7, NCIH460, and SF268. The complexes studied were designed to differ in geometrical parameters such as the position of the phenyl-group substituents and the nature of the substituents themselves for gathering information about the structure-activity relationships in the trans-complexes. The variation of the substituents turns to be crucial for their biological activity, as both pyridine-3- and pyridine-4-carboxylic acids in trans-position to both amine and isopropylamine ligands provided complexes which displayed no specificity toward any type of cell tested, while (hydroxymethyl)pyridine in trans-position to isopropylamine ligands led to complexes that were clearly more effective against the cell lines tested.

New trans-platinum drugs with phosphines and amines as carrier ligands induce apoptosis in tumor cells resistant to cisplatin.

Cisplatin resistance observed in some human tumors has prompted research in platinum derivatives that can circumvent this effect. Despite initial works reporting lack of activity of trans-platinum derivatives, complexes with the general formula PtCl2(L)(L') exhibit cytotoxic activity in cisplatin-sensitive and -resistant cell lines. Here we reported the chemical and biological properties of seven platinum complexes with PPh3 or PMe2Ph in trans to several amines. They show important antitumoral properties in tumor cell lines. Among the compounds, those with a replacement of an ammine ligand in the inactive trans-DDP by a phosphine ligand have an important enhancement of their cytotoxic activity. In SKOV3, no G1 nor G2/M accumulation was observed after treatments, and apoptosis was launched probably by a mechanism independent of classical checkpoints activation. Our data indicate that our compounds are not cross-resistant with cisplatin and might be promising agents in the treatment of tumors unresponsive to cisplatin.

Structural characterization, DNA interactions, and cytotoxicity of new transplatin analogues containing one aliphatic and one planar heterocyclic amine ligand.

We report in the present work new analogues of clinically ineffective transplatin in which one ammine group was replaced by aliphatic and the other by a planar heterocyclic ligand, namely trans-[PtCl(2)(isopropylamine)(3-(hydroxymethyl)-pyridine)], 1, and trans-[PtCl(2)(isopropylamine)(4-(hydroxymethyl)-pyridine)], 2. The new compounds, in comparison with parent transplatin, exhibit radically enhanced activity in tumor cell lines both sensitive and in particular resistant to cisplatin. Concomitantly, the DNA binding mode of 1 and 2 compared to parent transplatin and other antitumor analogues of transplatin in which only one ammine group was replaced is also different. The results also suggest that the reactions of glutathione and metallothionein-2 with compounds 1 and 2 do not play a crucial role in their overall biological effects. In addition, the monofunctional adducts of 1 and 2 are quenched by glutathione considerably less than the adducts of transplatin, which may potentiate cytotoxic effects of these new platinum complexes.

The role of p53 in the cellular toxicity by active trans-platinum complexes containing isopropylamine and hydroxymethylpyridine.

Despite some initial research that reported a lack of activity of trans geometry, complexes with general formula trans-[PtCl2(L)(L')] exhibit an important cytotoxic activity in cisplatin-sensitive and resistant cell lines. Based on the proposed mechanism of action for the trans-platinum compounds, they might form DNA adducts initiating a DNA-damage response and ultimately ending in the activation of the p53 protein. In the present work, we have studied the biochemical properties of the trans-[PtCl2(isopropylamine)(L)] complexes (where L is 3- or 4-(hydroxymethyl)-pyridine) against several cell lines and the relationship between cytotoxicity and the protein p53. Both complexes showed different antitumoral properties depending on the presence or absence of protein p53 in isogenic colon carcinoma HCT116 cell lines. Cell cycle studies with the complexes in these cell lines were performed to investigate their antitumoral activity. Apoptosis was observed to be launched from G1 or G2/M accumulations. Confocal microscopy showed the different behaviour of isogenic tumoral cell lines treated with the trans-platinum complexes. Our data suggest that small differences in the carrier ligands could play an important role in the overall biological effects. The body of the research regarding structure-activity relationships such as the different position of groups in the carrier ligands will provide new rational basis for the design of new platinum antitumor drugs.