Lew Pennington

This October roundup features key clinical updates, including FDA approvals, significant trial results for major drug candidates, the initiation of new clinical trials, and updates on halted studies.

CDI (Clostridioides difficile) infection is a leading cause of healthcare-associated diarrhea with significant morbidity and mortality, and with the rise of hypervirulent and resistant strains, novel and selective antibiotics to treat these infections are needed. Cadazolid, a hybrid antibiotic that combines pharmacophores of two classes of antibacterials, demonstrated potent activity in vitro against relevant C. difficile strains, while avoiding native gut flora. Additionally, the compound was designed to be gut-restricted, with minimal systemic circulation following PO dosing.

Sonrotoclax, BeiGene’s clinical-stage, orally bioavailable, next-generation inhibitor, targets both WT and mutated forms of the Bcl-2 protein by binding within a hydrophobic groove, similar to other inhibitors in its class. Explore this case study to see how sonrotoclax was rationally designed to potency against both WT and mutant Bcl-2 and address the limitations of first-generation inhibitors and more!

Here’s a quick recap of the top business news from October, including major deals, acquisitions, funding rounds, and strategic partnerships. If you missed any updates, here’s your chance to catch up on the most significant developments in the industry.

This article highlights key patents published in September 2024, covering a range of therapeutic targets and mechanisms. It includes Nurr1 and Nur77 modulators for oncology applications, STAT3 inhibitors and CRBN-based STAT3 degraders for modulating STAT3 signaling in cancer, and CDK2 molecular glue degraders for estrogen receptor-positive breast cancer resistant to CDK4/CDK6 inhibitors. Additionally, it features ERAP1 modulators for addressing autoimmune diseases, APOL1 inhibitors for APOL1-mediated kidney diseases, and novel NEK7 inhibitors targeting the NLRP3 inflammasome pathway.

HiberCell recently disclosed the discovery of HC-7366, a potential first-in-class, intentionally discovered, orally bioavailable, potent, selective, small-molecule kinase activator of GCN2. HC-7366 has now progressed to Ph. I trials to treat ccRCC and AML. This case study is a fantastic example of how to mitigate CYP3A4 inhibition and improve oral bioavailability via judicious choice of salt formulation.

Novartis' NLRP3 inhibitor, NVP-DFV890, features a unique sulfonimidamide motif designed to reduce hydrolysis relative to traditional sulfonylureas. This potent compound, with promising PK in humans, is advancing through multiple clinical studies, including Ph. II trials for coronary heart disease and knee osteoarthritis. Presented by Angela Mackay at the EFMC-ISMC 2024 joint conference in Rome, this overview covers NVP-DFV890's discovery, as well as its preclinical PK and PD data.

In this article, we present a curated selection of over 60 molecules from September that caught our attention, along with highlights of our top picks and insights into why they stand out.

Recently, a surge of (pre)clinical compounds inhibiting the NLRP3 inflammasome, often featuring a hexahydroindacene ring system, has emerged, including Nodthera’s ND-0796. In a push for new chemotypes, AZ and Mitsubishi Tanabe have disclosed their clinical compound, AZD4144, which is currently in Ph. I trials in healthy volunteers. The discovery story detailed their efforts to overcome PLD (phospholipidosis), genotoxicity, and hERG inhibition in a non-classical pharmacophore series. The discovery was presented by Anders Johansson at the EFMC-ISMC 2024 Meeting in Rome.

Infection with the malaria parasite, Plasmodium falciparum, is a leading cause of fatality in the tropical regions of the world, with >240M infections and >600K deaths each year, the majority of which are in sub-Saharan Africa. The need for new antimalarials is clear, given that over half of the world's population is at risk of infection, combined with the rise of resistance against current treatments. Novartis has played a key role in this fight and at the ACS Fall 2024 meeting in Denver, CO, they disclosed NVP-FVP954: a novel, fast-acting IV antimalarial for severe malaria.

Sovleplenib (HMPL-523) is an orally bioavailable Syk inhibitor being developed by HUTCHMED and is currently in Ph. II and Ph. III clinical trials for several autoimmune diseases. Derived from an HTS hit and SAR optimization, the discovery story of sovleplenib serves as an excellent case study on how to design a next-generation Syk inhibitor devoid of off-target kinase activity, mitigated hERG activity, and more.

BMS-986397 is a potential first-in-class CRBN-based selective CK1α molecular glue degrader. CK1α promotes tumor growth by enhancing MDM2 and MDMX degradation of the tumor suppressor p53. Since AML has a low TP53 mutation rate, activating the p53 pathway is a promising approach; however, p53 activators have faced challenges due to hematological toxicities. Targeting CK1α degradation offers an alternative approach. The BMS team sought to develop a CELMoD® for CK1α degradation. This article outlines the discovery of BMS-986397, as presented at the ACS Fall 2024 meeting in Denver, CO.

EOS-984 is an oral, potential first-in-class, highly selective ENT1 inhibitor from iTeos currently in clinical trials for advanced solid tumors. The drug, which was identified through SBDD and optimization of the vasodilator dilazep, targets the immunosuppressive effects of adenosine, which helps tumors evade immune detection. This is an excellent case study on the importance of understanding a molecule's bioactive conformation to reduce the entropy of binding and enhance potency.

Despite the remarkable emergence of HAART in the 1990s, the fight against HIV infection is by no means finished. At the ACS Fall 2024 meeting in Denver, CO, Gilead Sciences presented the structure and discovery story of elunonavir (GS-1156), a novel HIV protease inhibitor with remarkable metabolic stability and a human half-life exceeding two weeks. Based on BMS’ atazanavir, the compound incorporates structural elements inspired by Gilead’s HCV NS5A inhibitor program which led to ledipasvir, as “stabilizer” motifs to avoid the extensive CYP metabolism seen in current inhibitors.

BMS-986408 is an oral, dual DGK ⍺ and ζ inhibitor currently in a Ph. I/II trial in patients with solid tumors. The compound was identified stemming from a phenotypic screening approach, and subsequent target deconvolution revealed DGK to be the target. If approved, it would be a first-in-class intracellular checkpoint inhibitor of DGK. This is an excellent case study on how to overcome a DILI risk associated with BSEP inhibition, as well as how to improve solubility and PK properties of your compounds through the introduction of polarity, reduction of aromatic rings, and increase in f(sp3).

Arvinas’ ARV-471 is an orally bioavailable CRBN-based ER PROTAC degrader for treating patients with ER+/HER2-breast cancer and the first PROTAC to enter Ph. III clinical trials. This molecule one-pager serves as a reference guide, offering an overview of the scientific significance of Arvinas’ ARV-471 program. It includes links to key presentations, publications, patents, preclinical and clinical PK data summaries, and more.

This summary of September's major clinical updates features FDA approvals, drug withdrawals, anticipated regulatory decisions, notable trial results, new NDA submissions, clinical trial setbacks, and the initiation of new clinical trials.

In this article, you'll find a curated selection of >70 molecules from August that piqued our interest, highlights of some of our favorites, and explanations of why they're worth watching.

This article highlights the key drug discovery patents published in August 2024, including AKR1C3-dependent KARS (not KRAS!) inhibitors for NRF2/KEAP1-mutated cancers and DHX9 helicase inhibitors of MSI-high tumors. It also covers the development of MK2 degraders for inflammatory diseases and small molecule IL-17A inhibitors that show promise in modulating inflammation. Additionally, we cover Roche’s take on Revolution Medicines’ macrocyclic pan-KRAS inhibitors, which show improved PK profiles, and novel non-hydroxamate LpxC inhibitors for treating Gram-negative bacterial infections.

KEAP1 inhibition/NRF2 activation has been hotly pursued in recent years for immunology indications; however, in oncology, NRF2 degradation has been posited as a novel therapeutic mechanism for specific cancers. Vividion has already disclosed work on covalent KEAP1 inhibitors, but at the recent ACS Fall 2024 meeting, the structure and discovery story of their clinical oral covalent activator of KEAP1 were disclosed, identified through careful analysis of the data from their inhibitor screen.

Arvinas’ ARV-393 is an orally bioavailable PROTAC that degrades BCL6 via CRBN-mediated ubiquitination and proteasomal degradation intended for the treatment of NHL. At the AACR San Diego 2024 meeting, Arvinas disclosed the structure and discovery story of this molecule, which exhibits first-in-class potential. This article covers the key SAR observations that led to the invention of this orally bioavailable PROTAC®, its performance in a triple-hit, high-grade BCL and R-CHOP-resistant cell line, and why sustaining BCL6 knockdown beyond 24 hours was critical for the success of this program.

BridgeBio’s BBO-8520 is a selective, covalent KRAS(G12C) inhibitor which differentiates itself from the pack by engaging the (ON) state of the protein, potentially conferring increased clinical benefit in KRAS(G12C)-driven cancers, including overcoming resistance to current treatments. Disclosed at the 2024 AACR Annual Meeting in San Diego, is currently in a Ph. I trial in patients with advanced non-small-cell lung cancer. This article covers the structure, mechanism of action and preclinical efficacy that marks this compound out as one to watch.

During Drug Hunter’s Flash Talks, experts talk in-depth about hot topics in drug discovery. These experts also share insights beyond the subjects of their presentations, such as how they got inspired to become a drug hunter, what their favorite molecule is, what excites them most in drug discovery today, and what advice they wish they could give their younger selves. Here is a quick look at some of these insightful nuggets from Flash Talks hosted between January and August 2024.

PLX-4545 is an oral CRBN-based molecular glue degrader of IKZF2 in Ph. I trials. It potentially addresses anti-tumor immunity suppression within the TME, critical in checkpoint blocker resistance. Tumors use IKZF2 to regulate the function of regulatory T cells and inhibit effector T cells. IKZF2 depletion in regulatory T cells enhances the anti-tumor response. The discovery and structural data of PLX-4545 were presented by Kevin Freeman-Cook at the ACS Fall 2024 First-Time Disclosures session in Denver, CO. We are reporting the discovery story and its potential impact on immuno-oncology.

BAY 2925976 is a novel oral ARα2C antagonist developed by Bayer for the treatment of OSA (obstructive sleep apnea), a widespread condition affecting nearly one billion people globally. Despite the availability of mechanical treatments like CPAP, poor adherence rates highlight the need for more effective interventions. BAY 2925976 demonstrated a preclinical proof of concept for ARα₂C modulation as a potential therapeutic approach for OSA. In this article, we detail the discovery of BAY 2925976, as highlighted by Michael Hahn at the ACS Fall 2024 First-Time Disclosures session in Denver, CO.

In August 2024, seladelpar (LivdelziTM) became the first FDA-approved selective agonist of PPARδ (peroxisome proliferator-activated receptor δ), following an almost 20-year journey from the original discovery and patent publications. Originally developed by CymaBay in collaboration with Johnson & Johnson, approval was granted to Gilead Sciences following their February 2024 purchase of CymaBay Therapeutics for $4.3B. Seladelpar was approved as a second-line treatment for patients with primary biliary cholangitis.

The recently released WHO INN proposed names list includes the structure and name of Structure Therapeutics’ oral small molecule GLP-1R agonist, aleniglipron (GSBR-1290). Seemingly emerging from a “fast-follower” program based on Chugai/Eli Lilly’s orforglipron, the compound includes an unusual phosphine oxide motif and has shown positive results on plasma glucose levels and bodyweight in a Ph. IIa study.

Pfizer disclosed the structure and discovery of their oral small molecule BDK inhibitor/degrader, PF-07328948, during the ACS Fall 2024 First-Time Disclosures session in Denver. The team identified a thiophene carboxylic acid-based hit targeting an allosteric pocket on BDK. Through optimization, they overcame challenges such as potential IADRs and BDK-E2 complex stabilization. By manipulating the dihedral angle of the methoxy group, they enhanced binding interactions, verifying PF-07328948's unexpected mechanism of action in vivo. PF-07328948 is currently Ph. I trials.

Infection with the malaria parasite, Plasmodium falciparum, is a leading cause of fatality in the tropical regions of the world, with over 240M infections and >600k deaths each year. Currently, over half of the world population is at risk of infection and with the rise of resistance against current treatments, the need for new antimalarials is clear. At the ACS Fall 2024 conference in Denver, CO, Novartis outlined the structure and discovery story of NVP-IWY357, a novel antimalarial that has no cross-resistance to current drugs and the potential to achieve a single-dose cure.

This article highlights a patent application from Monte Rosa Therapeutics that discloses the biological activity of compounds that act as VAV1 molecular glue degraders, providing a summary of key data for selected molecules disclosed in the patent application.

In case you missed August’s business news, here’s a quick recap of five headlines, including an acquisition, three funding rounds, and a notable company closure.

Here’s a rundown of August’s key clinical developments, including FDA approvals, potential upcoming approvals, notable trial readouts, new NDA submissions, and pipeline realignments.

This article highlights a patent application from Constellation Pharmaceuticals that discloses the biological activity of compounds that act as TREX1 inhibitors, providing a summary of key data for selected molecules disclosed in the patent application.

This article highlights a patent application from AstraZeneca and Mitsubishi Tanabe, and Astellas Pharma that discloses the biological activity of compounds that act as NLRP3 inhibitors, providing a summary of key data for selected molecules disclosed in the patent application.

This article highlights a patent application from Arvinas that discloses the biological activity of compounds that act as tau-targeting heterobifunctional degraders, providing a summary of key data for selected molecules disclosed in the patent application.

This article highlights a patent application from Puhe BioPharma that discloses the biological activity of compounds that act as WRN helicase inhibitors, providing a summary of key data for selected molecules disclosed in the patent application.

The highly anticipated First Time Disclosures session, attended by over 400 conferees, both in-person and virtually, was organized by the MEDI Division of ACS at the ACS Fall 2024 meeting in Denver. This session unveiled 13 fascinating small molecules currently in clinical development. The two-part event showcased innovations ranging from Novartis’ pentafluorosulfanyl-containing antimalarial, IWY357, to Vividion’s covalent activator of KEAP1, which targets NRF2 degradation. This article captures the essence of the session, providing the structures and targets of the novel molecules disclosed.

Kymera's KT-474 is the first oral heterobifunctional degrader to demonstrate activity in clinical trials outside cancer. This molecule one-pager serves as a reference guide, offering an overview of the scientific significance of Kymera's KT-474 program. It includes links to key presentations, publications, patents, preclinical and clinical PK data summaries, and more.

To get you up to speed, here’s a recap of July’s molecules on the move, including potential upcoming approvals, key interim trial readouts, new IND submissions, and trial setbacks.

In case you missed anything while you were away on summer holiday, here’s a recap of six notable deals from July to get you up to speed.

To choose Molecules of the Month for June, our team reviewed hundreds of molecules from thousands of papers, press releases, conference presentations, and other sources. In this article, you'll find a curated selection of over 60 additional molecules from June that piqued our interest, along with highlights of some of our favorites and explanations of why they're worth keeping an eye on.

DILI is a leading cause of acute liver failure, accounting for half of these cases and often resulting in drug withdrawals. Understanding and managing DILI risk as a medicinal chemist involves exploring the intricate interplay among properties and structural features. In this article, we provide a medicinal chemist's perspective on the current understanding of DILI mechanisms, highlight cutting-edge assay developments for a holistic assessment, and discuss strategies for predicting DILI risks.

Minipigs have recently gained prominence as an alternative non-rodent in vivo model for pharmacokinetic (PK), efficacy, and toxicology studies supporting human dose predictions. This article provides an overview of the use of minipigs in small molecule preclinical drug discovery research, tracing their historical background and outlining practical considerations for selecting them in studies focusing on hepatic metabolism, oral bioavailability, CNS penetration, and toxicology. It highlights minipigs' unique advantages and makes a compelling case for their continued use in preclinical research.