Society for birth defects research and prevention's multidisciplinary research needs workshop 2022: A call to action.

The Society for Birth Defects Research and Prevention (BDRP) strives to understand and protect against potential hazards to developing embryos, fetuses, children, and adults by bringing together scientific knowledge from diverse fields. The theme of 62nd Annual Meeting of BDRP, "From Bench to Bedside and Back Again", represented the cutting-edge research areas of high relevance to public health and significance in the fields of birth defects research and surveillance. The multidisciplinary Research Needs Workshop (RNW) convened at the Annual Meeting continues to identify pressing knowledge gaps and encourage interdisciplinary research initiatives. The multidisciplinary RNW was first introduced at the 2018 annual meeting to provide an opportunity for annual meeting attendees to participate in breakout discussions on emerging topics in birth defects research and to foster collaboration between basic researchers, clinicians, epidemiologists, drug developers, industry partners, funding agencies, and regulators to discuss state-of-the-art methods and innovative projects. Initially, a list of workshop topics was compiled by the RNW planning committee and circulated among the members of BDRP to obtain the most popular topics for the Workshop discussions. Based on the pre-meeting survey results, the top three discussion topics selected were, A) Inclusion of pregnant and lactating women in clinical trials. When, why, and how? B) Building multidisciplinary teams across disciplines: What cross-training is needed? And C) Challenges in applications of Artificial Intelligence (AI) and machine learning for risk factor analysis in birth defects research. This report summarizes the key highlights of the RNW workshop and specific topic discussions.

Results from oral gavage carcinogenicity studies of ruxolitinib in Tg.rasH2 mice and Sprague-Dawley (Crl:CD) rats.

Ruxolitinib is a selective and potent inhibitor of Janus kinase (JAK) 1 and JAK2. It is approved for the treatment of patients with intermediate or high-risk myelofibrosis, or those with polycythemia vera who have had an inadequate response to or are intolerant of hydroxyurea. To investigate its carcinogenic potential, ruxolitinib was administered by oral gavage once daily to Tg.rasH2 mice for 6 months at doses of 15, 45 or 125 mg/kg/day, and to Sprague-Dawley (Crl:CD) rats for 2 years at 10, 20 or 60 mg/kg/day. Ruxolitinib had no effect on survival, and did not increase the incidence of any neoplastic findings in either species. Exposure (AUC) was similar to or exceeded that associated with therapeutic use. Lymphoid depletion and a decrease in extramedullary hematopoiesis in the spleen occurred in rats, which were attributed to the pharmacologic activity of ruxolitinib. In Tg.rasH2 mice, increased inflammation in the nasal cavity was observed. Dose-dependent decreases in a number of spontaneous neoplastic/preneoplastic lesions were observed in rats, including mammary tumors in females, adrenal pheochromocytomas in males, hepatocellular adenomas/carcinomas in males, and hepatic basophilic (males and females) and eosinophilic (males) foci. Peribiliary fibrosis was also decreased. Clear cell foci in the liver were increased in females. Based on the results of these studies, ruxolitinib is not considered to be carcinogenic.

Effects of the opioid analgesic oxymorphone hydrochloride on reproductive function in male and female rats.

BACKGROUND: Endogenous opioids seem to regulate hypothalamic gonadotropin release in both males and females, as evidenced by the effects of opioid agonists and antagonists on LHRH release and reproductive hormone levels. The effects of long-term oral administration of opioid analgesics on reproductive function have not been well characterized. METHODS: The reproductive effects of oxymorphone, a potent opioid agonist, were investigated in male and female Crl:CD(SD) IGS BR rats at oral doses of 0, 5, 10, and 25 mg/kg/day (25 animals/sex/group). Males were treated for approximately 9 weeks (mated after 4 weeks of dosing). Females were treated for 14 days before mating, and through Gestation Day (GD) 7. Estrous cycling was evaluated during the premating period. On GD15, pregnancy status and the numbers of corpora lutea, implantation sites, live and dead embryos were determined. Epididymal and testicular sperm counts and epididymal sperm motility and morphology were evaluated in males. RESULTS: Two males given 25 mg/kg/day died. Behavioral changes and deficits in body weight gain occurred at all doses. There were no effects of oxymorphone on reproductive function or sperm parameters in males. The estrous cycle was prolonged in females given 25 mg/kg/day (mean of 5.3 vs. 4.3 days in controls). A small, but consistent decrease in the numbers of corpora lutea (with associated decreases in implantation sites and embryos) occurred in females given > or =10 mg/kg/day. There were no effects on mating or fertility in females. CONCLUSIONS: Oxymorphone seems to partially inhibit ovulation in female rats, with no significant effects on male reproductive outcome.

Evidence that oxymorphone-induced increases in micronuclei occur secondary to hyperthermia.

Oxymorphone is a potent opioid analgesic. Oral administration of oxymorphone to rats at doses >or= 20 mg/kg and mice at 500 mg/kg produced an increase in micronucleated polychromatic erythrocytes (MPCEs). Oxymorphone does not produce chromosome aberrations in vitro, suggesting that the increased MPCEs in vivo may involve indirect mechanisms. Opioids are known to affect thermoregulatory mechanisms. Changes in body temperature can increase the incidence of MPCEs in rodents. Studies were conducted to examine the relationship between increased MPCEs in rats given oxymorphone and changes in body temperature. Single oral doses of oxymorphone associated with increased MPCEs (20 and 40 mg/kg) also produced a marked, rapid increase in body temperature. When animals were pretreated with sodium salicylate, peak body temperature was lower and returned to baseline more quickly than when oxymorphone was given alone. MPCEs were evaluated in rats after administration of oxymorphone (40 mg/kg) alone or following pretreatment with an oral dose of sodium salicylate. Oxymorphone alone produced a statistically significant increase in the incidence of MPCEs (3.6 per 1000 polychromatic erythrocytes vs. 0.4 in controls). The number of MPCEs in animals pretreated with sodium salicylate was similar to controls. Sodium salicylate alone had no effect on the number of MPCEs. Systemic oxymorphone exposure was not affected by sodium salicylate pretreatment; maximum plasma concentration (C(max)) and area-under-the-curve values were similar after administration of oxymorphone alone or following pretreatment with sodium salicylate. These results indicate that the increased incidence of MPCEs following oxymorphone administration is directly related to increased body temperature.

Oxymorphone hydrochloride, a potent opioid analgesic, is not carcinogenic in rats or mice.

Despite their long history of chronic use, little information is available regarding the carcinogenicity of opioid analgesics. Oxymorphone is a potent morphinan-type mu-opioid analgesic used for treatment of moderate-to-severe pain. Oxymorphone was tested for carcinogenicity in Crl:CD IGS BR rats and CD-1 mice. Oxymorphone hydrochloride was administered orally once daily for 2 years to rats at doses of 2.5, 5 and 10 mg/kg/day (males) and 5, 10 and 25 mg/kg/day (females), and mice at 10, 25, 75 and 150 mg/kg/day (65 animals per sex per group; 100 animals per sex in controls). In rats, survival was generally higher than controls in oxymorphone-treated groups, attributable to lower body weight gain. In mice, survival was generally higher than controls in females at all doses and males given < or = 25 mg/kg/day but lower in males given > or = 75 mg/kg/day due to a high incidence of obstructive uropathy. Opioid-related clinical signs and reduced body weight gain occurred in both species throughout the study. Nonneoplastic findings associated with oxymorphone pharmacology included ocular and pulmonary changes in rats considered secondary to inhibition of blinking and mydriasis, and antitussive activity, respectively, and urinary tract and renal findings in mice considered secondary to urinary retention. There was no target organ toxicity, and no increase in any neoplastic lesions attributed to oxymorphone. Plasma oxymorphone levels achieved in these studies exceeded those in patients taking high therapeutic doses of oxymorphone (Area under the curve [AUC(0-24 h)] values up to 5.6-fold and 64-fold in rats and mice, respectively). Oxymorphone is not considered to be carcinogenic in rats or mice under the conditions of these studies.

Neurobehavioral assessment: a survey of use and value in safety assessment studies.

This report describes the results of a survey designed to evaluate the contribution of F1 neurobehavioral testing to hazard identification and characterization in safety assessment studies. (To review the details of the distributed survey, please see the supplementary data for this article on the journal's Web site.) The survey provided information about studies completed in industrial laboratories in the United States, Europe, and Japan since 1990 on 174 compounds. The types of compounds included were pharmaceutical (81%), agricultural (7%), industrial (1%), or were undefined (10%). Information collected included the intended use of the test agent, general study design and methodology, the types and characteristics of F1 behavioral evaluations, and the frequency with which agents affected neurobehavioral parameters in comparison to other F0 and F1 generation parameters. F1 general toxicology parameters such as mortality, pre- and postweaning body weight, and food intake were assessed in most studies and were affected more frequently than other parameters by the test agents. F1 behavioral parameters were assessed less consistently across studies, and were less frequently affected by the agents tested. Although affected by agents less often than general toxicology parameters, F1 behavioral parameters along with other parameters defined the no-observed-effect level (NOEL) in 17/113 (15%) of studies and solely defined the NOEL in 3/113 (2.6%) of studies. Thus, F1 behavioral parameters sometimes improved on the standard toxicological measures of hazard identification. While not detecting agent effects as readily as some measures, the F1 behavioral parameters provide information about agent effects on specialized functions of developing offspring not provided by other standard measures of toxicity. The survey results emphasize the need for further research into the methods of behavioral assessment as well as the mechanisms underlying the neurobehavioral alterations.