Ileocolonic-Targeted JAK Inhibitor: A Safer and More Effective Treatment for Inflammatory Bowel Disease

Exploring the interactions of JAK inhibitor and S1P receptor modulator drugs with the human gut microbiome: Implications for colonic drug delivery and inflammatory bowel disease

The gut microbiota is a complex ecosystem, home to hundreds of bacterial species and a vast repository of enzymes capable of metabolising a wide range of pharmaceuticals. Several drugs have been shown to affect negatively the composition and function of the gut microbial ecosystem. Janus Kinase inhibitors and Sphingosine-1-phosphate receptor modulators are drugs recently approved for inflammatory bowel disease through an immediate release formulation and would potentially benefit from targeted colonic targeted delivery to enhance the local drug concentration at the diseased site. However, their impact on the human gut microbiota and susceptibility to bacterial metabolism remain unexplored. With the use of calorimetric, optical density measurements, and metagenomics next-generation sequencing, we show that JAK inhibitors have a minor impact on the composition of the human gut microbiota, while ozanimod exerts a significant antimicrobial effect, leading to a prevalence of the Enterococcus genus and a markedly different metabolic landscape when compared to the untreated microbiota. Moreover, ozanimod is the only drug subject to enzymatic degradation by the human gut microbiota sourced from six healthy donors.. Overall, given the crucial role of the gut microbiome in health, screening assays to investigate the interaction of drugs with the microbiome should be encouraged for the pharmaceutical industry as a standard in the drug discovery and development process.

An overview on recent approaches for colonic drug delivery systems

Colon-targeted drug delivery systems have garnered significant interest as potential solutions for delivering various medications susceptible to acidic and catalytic degradation in the gastrointestinal (GI) tract or as a means of treating colonic diseases naturally with fewer overall side effects. The increasing demand for patient-friendly drug administration underscores the importance of colonic drug delivery, particularly through noninvasive methods like nanoparticulate drug delivery technologies. Such systems offer improved patient compliance, cost reduction, and therapeutic advantages. This study places particular emphasis on formulations and discusses recent advancements in various methods for designing colon-targeted drug delivery systems and their medicinal applications.

A Phase I, Randomized, Multi-Dose Study to Evaluate the Enteric Selectivity and Safety of JAK Inhibitor, Lorpucitinib, in Healthy Participants

Janus kinase (JAK) signaling has been implicated in human inflammatory diseases, including psoriasis, rheumatoid arthritis, and inflammatory bowel disease. Lorpucitinib (JNJ-64251330) is an oral, small molecule, pan-JAK inhibitor. Unlike systemic JAK antagonists, lorpucitinib was found to have enteric (gut)-selective properties, providing possible applications in diseases of the human gastrointestinal tract. Here, lorpucitinib was evaluated in a phase I, two-part, dosing study (NCT04552197) to assess pharmacokinetics, pharmacodynamic biomarkers, and safety in healthy participants. In part 1, 24 participants were randomized to 1 of 4 treatment arms receiving either lorpucitinib (30 mg daily, 30 mg every 12 hours (q12h), or 75 mg q12h) or tofacitinib (5 mg q12h) for 5 days. Part 2 was a food-effect study in which 12 participants received a single 75-mg dose of lorpucitinib under either fasting or fed conditions. In part 1, plasma and gut tissue concentrations of lorpucitinib showed approximately dose-proportional increases. At all doses, lorpucitinib concentrations were significantly higher (392- to 1928-fold) in the gut mucosal biopsies vs. the corresponding plasma samples, demonstrating high enteric selectivity and significantly exceeding both the tissue concentrations (> 200-fold) and tissue/plasma ratios observed with tofacitinib. JAK inhibition in biopsies was confirmed via reduction in pSTAT-3 levels. In part 2, lorpucitinib plasma concentrations were detectable but at low levels, with no statistical differences in PK parameters between the fed and fasted groups. Lorpucitinib was safe and well-tolerated, and the data may be useful in designing studies to evaluate lorpucitinib in patients with JAK/STAT-driven gastrointestinal diseases.

Changes in HLA-B27 Transgenic Rat Fecal Microbiota Following Tofacitinib Treatment and Ileocecal Resection Surgery: Implications for Crohn's Disease Management

The therapeutic management of Crohn's disease (CD), a chronic relapsing-remitting inflammatory bowel disease (IBD), is highly challenging. Surgical resection is sometimes a necessary procedure even though it is often associated with postoperative recurrences (PORs). Tofacitinib, an orally active small molecule Janus kinase inhibitor, is an anti-inflammatory drug meant to limit PORs in CD. Whereas bidirectional interactions between the gut microbiota and the relevant IBD drug are crucial, little is known about the impact of tofacitinib on the gut microbiota. The HLA-B27 transgenic rat is a good preclinical model used in IBD research, including for PORs after ileocecal resection (ICR). In the present study, we used shotgun metagenomics to first delineate the baseline composition and determinants of the fecal microbiome of HLA-B27 rats and then to evaluate the distinct impact of either tofacitinib treatment, ileocecal resection or the cumulative effect of both interventions on the gut microbiota in these HLA-B27 rats. The results confirmed that the microbiome of the HLA-B27 rats was fairly different from their wild-type littermates. We demonstrated here that oral treatment with tofacitinib does not affect the gut microbial composition of HLA-B27 rats. Of note, we showed that ICR induced an intense loss of bacterial diversity together with dramatic changes in taxa relative abundances. However, the oral treatment with tofacitinib neither modified the alpha-diversity nor exacerbated significant modifications in bacterial taxa induced by ICR. Collectively, these preclinical data are rather favorable for the use of tofacitinib in combination with ICR to address Crohn's disease management when considering microbiota.

Impact of Peptide Structure on Colonic Stability and Tissue Permeability

Most marketed peptide drugs are administered parenterally due to their inherent gastrointestinal (GI) instability and poor permeability across the GI epithelium. Several molecular design techniques, such as cyclisation and D-amino acid (D-AA) substitution, have been proposed to improve oral peptide drug bioavailability. However, very few of these techniques have been translated to the clinic. In addition, little is known about how synthetic peptide design may improve stability and permeability in the colon, a key site for the treatment of inflammatory bowel disease and colorectal cancer. In this study, we investigated the impact of various cyclisation modifications and D-AA substitutions on the enzymatic stability and colonic tissue permeability of native oxytocin and 11 oxytocin-based peptides. Results showed that the disulfide bond cyclisation present in native oxytocin provided an improved stability in a human colon model compared to a linear oxytocin derivative. Chloroacetyl cyclisation increased native oxytocin stability in the colonic model at 1.5 h by 30.0%, whereas thioether and N-terminal acetylated cyclisations offered no additional protection at 1.5 h. The site and number of D-AA substitutions were found to be critical for stability, with three D-AAs at Tyr, Ile and Leu, improving native oxytocin stability at 1.5 h in both linear and cyclic structures by 58.2% and 79.1%, respectively. Substitution of three D-AAs into native cyclic oxytocin significantly increased peptide permeability across rat colonic tissue; this may be because D-AA substitution favourably altered the peptide's secondary structure. This study is the first to show how the strategic design of peptide therapeutics could enable their delivery to the colon via the oral route.

Colonic drug delivery: Formulating the next generation of colon-targeted therapeutics

Colonic drug delivery can facilitate access to unique therapeutic targets and has the potential to enhance drug bioavailability whilst reducing off-target effects. Delivering drugs to the colon requires considered formulation development, as both oral and rectal dosage forms can encounter challenges if the colon's distinct physiological environment is not appreciated. As the therapeutic opportunities surrounding colonic drug delivery multiply, the success of novel pharmaceuticals lies in their design. This review provides a modern insight into the key parameters determining the effective design and development of colon-targeted medicines. Influential physiological features governing the release, dissolution, stability, and absorption of drugs in the colon are first discussed, followed by an overview of the most reliable colon-targeted formulation strategies. Finally, the most appropriate in vitro, in vivo, and in silico preclinical investigations are presented, with the goal of inspiring strategic development of new colon-targeted therapeutics.