Sandra D. Newman

Challenges of drug discovery in novel target space. The Discovery and Evaluation of PF-3893787: A Novel Histamine H4 Receptor Antagonist

We describe the development of novel benzimidazoles as small molecule histamine H4 receptor (H4R) antagonists and their profiling in rat early toxicity studies. The discovery and optimisation of a second series of pyrimidine based antagonists is then described culminating in the identification of the clinical development candidate 13 (PF-3893787). The pre-clinical profile of 13 (PF-3893787) is presented including the development of a translatable biomarker. Our pragmatic approach to target selection, safety assessment, and testing for efficacy faced numerous challenges and we share a number of lessons which the team learned and which will assist us and others in future drug discovery projects.

4-Amino-2-(aryl)-butylbenzamides and Their conformationally constrained analogues. Potent antagonists of the human neurokinin-2 (NK2) receptor

A library, evaluating a range of piperazines, piperidines and acyclic amines, as replacements for the 4-hydroxy-4-phenylpiperidine moiety in lead (1b) was prepared. These efforts identified the 4-((N)-benzimidazolone)piperidine analogue (2a) which was further optimised using classical single-compound synthesis to yield the 3-((N)-morpholino)azetidine (2j). Conformationally constrained analogues of (2j), generally offered no potency advantage in this particular series.

Comparison of the Non‐Nucleoside Reverse Transcriptase Inhibitor Lersivirine with its Pyrazole and Imidazole Isomers

Lersivirine is a potent non‐nucleoside reverse transcriptase inhibitor with exceptional mutant resilience. Here, we compare the pharmacological and pharmacokinetic profile of lersivirine with its pyrazole and imidazole isomers and briefly explore the profile of these series. This work establishes lersivirine as the outstanding molecule in this set.

Optimization of 5‐Aryloxyimidazole Non‐Nucleoside Reverse Transcriptase Inhibitors

A major problem associated with non‐nucleoside reverse transcriptase inhibitors (NNRTIs) for the treatment of HIV is their vulnerability to mutations in the allosteric binding site of reverse transcriptase that can result in the development of a resistant virus. Herein we present the optimization of a series of 5‐aryloxy imidazoles, which possess a balanced pharmacological profile against both wild‐type enzyme and the clinically relevant mutations K103N and Y181C. Subtle structural changes were used to probe structure–activity relationships relating to both potency and metabolic stability, which led to an imidazole derivative with an impressive overall profile.

Optimized glucuronidation of dual pharmacology β-2 agonists/M3 antagonists for the treatment of COPD

‘Inhalation by design’ concepts were developed to create novel dual pharmacology β-2 agonists-M3 antagonists, for the treatment of chronic obstructive pulmonary disorder. A key feature of this work is the combination of balanced potency and pharmacological duration with optimised glucuronidation through the incorporation of metabolically vulnerable phenols.