Discovery of a Potent and Selective Tyrosine Kinase 2 Inhibitor: TAK-279

TYK2 is a key mediator of IL12, IL23, and type I interferon signaling, and these cytokines have been implicated in the pathogenesis of multiple inflammatory and autoimmune diseases such as psoriasis, rheumatoid arthritis, lupus, and inflammatory bowel diseases. Supported by compelling data from human genome-wide association studies and clinical results, TYK2 inhibition through small molecules is an attractive therapeutic strategy to treat these diseases. Herein, we report the discovery of a series of highly selective pseudokinase (Janus homology 2, JH2) domain inhibitors of TYK2 enzymatic activity. A computationally enabled design strategy, including the use of FEP+, was instrumental in identifying a pyrazolo-pyrimidine core. We highlight the utility of computational physics-based predictions used to optimize this series of molecules to identify the development candidate 30, a potent, exquisitely selective cellular TYK2 inhibitor that is currently in Phase 2 clinical trials for the treatment of psoriasis and psoriatic arthritis.

Orally active fumagillin analogues: transformations of a reactive warhead in the gastric environment

Semisynthetic analogues of fumagillin, 1, inhibit methionine aminopeptidase-2 (MetAP2) and have entered the clinic for the treatment of cancer. An optimized fumagillin analogue, 3 (PPI-2458), was found to be orally active, despite containing a spiroepoxide function that formed a covalent linkage to the target protein. In aqueous acid, 3 underwent ring-opening addition of water and HCl, leading to four products, 4-7, which were characterized in detail. The chlorohydrin, but not the diol, products inhibited MetAP2 under weakly basic conditions, suggesting reversion to epoxide as a step in the mechanism. In agreement, chlorohydrin 6 was shown to revert rapidly to 3 in rat plasma. In an ex vivo assay, rats treated with purified acid degradants demonstrated inhibition of MetAP2 that correlated with the biochemical activity of the compounds. Taken together, the results indicate that degradation of the parent compound was compensated by the formation of active equivalents leading to a pharmacologically useful level of MetAP2 inhibition.

Assessment and treatment of terminal restlessness in the hospitalized adult patient with cancer

Terminal restlessness affects a large proportion of patients with cancer at the end of life. It has many different risk factors, presentations, and causes. Management consists of keen assessment, identification and reversal of the causes, and treatment by a combination of pharmacological, environmental, and spiritual interventions.

Design and synthesis of an irreversible dopamine-sparing cocaine antagonist

Cocaine is a powerful reinforcer and stimulant that binds to specific recognition sites associated with monoamine transporters in the mammalian brain. The search for a functional antagonist to the addictive properties of cocaine has focused on the discovery of a molecule that can inhibit cocaine binding to the dopamine transporter (DAT) but continue to allow dopamine transport by the DAT. No such dopamine-sparing cocaine antagonist has been reported and it is becoming evident that dopamine-sparing antagonism of the pharmacological effects of cocaine by a classical antagonist may not be possible. Herein we present a new concept for the design of dopamine-sparing cocaine antagonists. A unique approach is utilized to deliver an inhibitor that binds irreversibly to the DAT, then cleaves and leaves behind a small fragment attached to the DAT that blocks access by cocaine but permits dopamine transport. The design of these compounds takes advantage of a cysteinyl sulfhydryl group in the DAT. This group is hypothesized to attack the incoming inhibitor and lead to selective inhibition of the cocaine binding site while sparing dopamine transport. This concept of a mechanism based irreversible dopamine-sparing cocaine antagonist has now been demonstrated to be viable and, as example, the unsaturated 6 showed inhibition of cocaine (63%) at the DAT after 24h incubation, while at that point considerably less inhibition of dopamine is manifested (23%). In contrast, the epoxide 7 showed a greater inhibition of dopamine reuptake than cocaine binding at 24h (68% versus 18%).

Is vaginal birth after cesarean safe? Experience at a community hospital

OBJECTIVE

We sought to evaluate the effectiveness and safety of promoting a trial of labor after prior cesarean birth in a community hospital.

STUDY DESIGN

A 4-year prospective cohort study was conducted of all patients who had prior cesarean births (N = 1481). A comparison of outcomes was performed between those who elected repeat cesarean delivery (n = 727) and those who attempted a trial of labor after previous cesarean(s) (n = 754).

RESULTS

We found that the vaginal birth after cesarean attempt rate was 50.9% and declined significantly during the last 2 years of the study. The elective repeat cesarean rate was 49.1% and increased significantly during the last 2 years of the study. In addition, we found that neonatal outcomes were similar, with the exception of 2 neonatal deaths caused by uterine rupture. Twelve uterine ruptures occurred (1.6%), and 11 of the 12 ruptures involved either induction or augmentation of labor, or both.

CONCLUSIONS

A trial of vaginal birth after cesarean is safe provided that induction of labor is not used. The uterine rupture rate of 1.6% is higher than reported in the literature; this may reflect underreporting by community hospitals.

Isolated elevation of serum alkaline phosphatase level in an uncomplicated pregnancy: a case report

Serum level of alkaline phosphatase of placental origin was increased >10-fold in a 28-year-old pregnant woman. Repeated abdominal ultrasonographic scans yielded negative results for hepatobiliary disease. After delivery of a healthy baby, the placenta showed no major pathologic characteristics, and the alkaline phosphatase level returned to the reference range.

Comparison of obstetric outcome of a primary-care access clinic staffed by certified nurse-midwives and a private practice group of obstetricians in the same community

OBJECTIVE

The purpose of this study was to compare the obstetric outcome of a primary-care access clinic staffed by certified nurse-midwives, supervised by a private practice group of four obstetricians, with the obstetric outcome of that group's private practice patients.

STUDY DESIGN

A retrospective cohort study was performed. Obstetric outcome of 496 clinic patients was compared with that of 611 private patients in the same community from Aug. 1, 1991, to March 31, 1994.

RESULTS

Obstetric outcomes as measured by (1) perinatal morbidity and mortality, (2) Apgar score, (3) birth weights, and (4) prematurity rates were comparable between the two groups. Significant was the cesarean section rate of 13.1% (10.5% primary) for the clinic patients and 26.4% (18.5% primary) for the private patients and the high percentage (81.8%) of private patients who elected to have repeat cesarean sections.

CONCLUSIONS

(1) Low-income, uninsured, and underinsured women who have access to excellent prenatal care with supervised certified nurse-midwives can have obstetric outcomes similar to women having prenatal care with private obstetricians. (2) Prenatal care with supervised certified nurse-midwives can reduce the cesarean section rate without compromising infant outcome. (3) Utilization of certified nurse-midwives supervised by obstetricians may provide the optimum model for perinatal care, particularly for those women who are at high risk because of social and economic factors and who are currently underserved.

Obstetric performance of patients after oocyte donation

OBJECTIVE

The purpose of this study was to evaluate the obstetric performance of patients after oocyte donation.

STUDY DESIGN

A review of five patients in the author's private practice who underwent successful donation with conception and a literature review specific to obstetric outcome were undertaken.

RESULTS

All five patients were delivered of healthy infants; however, significant maternal complications occurred, particularly in two patients with twin gestations. A literature review substantiates increased incidence of (1) multiple gestation, (2) pregnancy-induced hypertension, (3) placenta previa, (4) preterm labor, and (5) cesarean birth. Infant outcomes, however, were good.

CONCLUSIONS

Women with premature ovarian failure and women over 40 years old can successfully conceive with oocyte and preembryo donation and successfully deliver healthy infants. More attention needs to be directed at maternal performance, particularly in those women over 40 years old.

Elective manual exploration of the uterus after delivery: a study and review

One hundred patients who had elective manual exploration of the uterus at the time of delivery were compared with a control group of 100 patients with regard to febrile morbidity and blood loss at delivery. Febrile morbidity was quantitated with the Fever Index, and postpartum blood loss was quantitated by subtracting the two-day postpartum hemoglobin from the admission hemoglobin. The patient population encompassed only normal spontaneous vaginal deliveries without complications. The manually explored group had less febrile morbidity and less blood loss; however, this was not statistically significant. Although this study cannot conclude that routine elective manual exploration of the uterus should be done after expulsion of the placenta, it does demonstrate the safety of the procedure.