Pregnancy Outcomes in Patients Exposed to OnabotulinumtoxinA Treatment: A Cumulative 29-Year Safety Update.

BACKGROUND AND OBJECTIVES: A previous publication of pregnancy outcomes in onabotulinumtoxinA-exposed mothers demonstrated that the prevalence of major fetal defects (0.9%, 1/110) was comparable with background rates in the general population. There is continued interest to better understand the safety of onabotulinumtoxinA during pregnancy. This analysis evaluated pregnancy outcomes after onabotulinumtoxinA exposure to provide a cumulative 29-year update. METHODS: The Allergan Global Safety Database was searched from January 1, 1990, to December 31, 2018. Data from women (younger than 65 years or unknown) during pregnancy or ≤3 months before conception treated with onabotulinumtoxinA were assessed to estimate birth defect prevalence rates of live births only from prospective pregnancies. RESULTS: Of 913 pregnancies, 397 (43.5%) were eligible with known outcomes. Maternal age was known in 215 pregnancies: 45.6% were 35 years or older. Indication was known in 340 pregnancies: most frequent were aesthetic (35.3%) and migraine/headache (30.3%). The timing of exposure was known in 318 pregnancies: 94.6% were before conception or during the first trimester. OnabotulinumtoxinA dose information was known in 242 pregnancies; most (83.5%) were exposed to <200 U. Of 195 prospective pregnancies with 197 fetuses, there were 152 (77.2%) live births and 45 (22.8%) fetal losses (32 spontaneous, 13 elective). Of 152 live births, 148 (97.4%) had normal outcomes and 4 had abnormal outcomes. Among the 4 abnormal outcomes, there were 1 major birth defect, 2 minor fetal defects, and 1 birth complication. The prevalence rate for overall fetal defects was 2.6% (4/152, 95% CI 1.0%-6.6%) and 0.7% (1/152, 95% CI 0.1%-3.6%) for major fetal defects (3%-6% in the general population). Among cases of live births and known determinable exposure times, there was 1 birth defect with preconception exposure and 2 with first-trimester exposure. DISCUSSION: Although subject to reporting bias due to the nature of the postmarketing database review, this 29-year retrospective analysis of safety data in pregnant women exposed to onabotulinumtoxinA demonstrates that the prevalence rate of major fetal defects among live births is consistent with the rates reported in the general population. Although there are limited data available for second-trimester and third-trimester exposure, this updated and expanded safety analysis provides important real-world evidence to health care providers and their patients. CLASSIFICATION OF EVIDENCE: This analysis provides Class III data that demonstrate that the prevalence rate of major fetal defects among live births subsequent to in utero onabotulinumtoxinA exposure is comparable with the reported background rates.

Linaclotide utilization and potential for off-label use and misuse in three European countries.

Introduction: Linaclotide is approved for adults with moderate-to-severe irritable bowel syndrome (IBS) with constipation (IBS-C). Linaclotide is not indicated for weight loss or for patients with inflammatory bowel disease (IBD); it is contraindicated in patients with mechanical bowel obstruction (MBO). Some patients with obesity or eating disorders (ED) may use linaclotide off-label for weight loss or as a laxative. Objectives: To describe the use of linaclotide in clinical practice, including patients with potential for off-label use or misuse. Methods: Post-authorization safety study conducted in three databases from the linaclotide launch date to 2017: the Clinical Practice Research Datalink in the United Kingdom (UK), the Information System for Research in Primary Care database in Spain and the linked Patient, Prescription and Causes of Death Registries in Sweden. Cohorts of patients were identified as having IBS using diagnostic and treatment codes; IBS subtypes were identified using symptoms and treatment codes; patients with obesity, ED, MBO, and IBD were identified using diagnostic codes or body mass index. Results: There were 1319, 1981, and 5081 linaclotide users from the United Kingdom, Spain, and Sweden with a median age of 45, 57, and 51 years, respectively; most were females. In the United Kingdom, Spain, and Sweden, respectively: 59.0%, 60.3%, and 31.3% of linaclotide users had an IBS diagnosis recorded, and among those, 68.8%, 61.3%, and 92.7% were classified as IBS-C. The proportions of linaclotide users considered at risk for potential off-label use for weight loss or as a laxative were 17.1%, 29.7%, and 1.7%, and the proportions of users considered at risk of misuse due to a history of MBO or IBD were 3.5%, 4.6%, and 5.7% in the United Kingdom, Spain, and Sweden, respectively. Conclusions: Potential linaclotide off-label use and misuse appears limited, as evidenced by the small sizes of the patient subgroups at risk for off-label use and misuse.