Switching patterns of immediate-release forms of generic mixed amphetamine salts products among privately and publicly insured individuals aged 15-64 years in the United States, 2013-2019.

PURPOSE: Immediate-release forms of generic mixed amphetamine salts (MAS) have been the subject of passive surveillance reports signaling lack of effectiveness. We examined switching patterns that might suggest whether long-term users of specific MAS are more likely to switch away or switch back after use of the MAS of interest in the FDA's Sentinel Distributed Database. METHODS: We required at least 60-day continuous supply of selected MAS grouped by Abbreviated New Drug Application (ANDA) to describe patterns of switching away from and to generics approved under the ANDAs of interest among individuals ages 15-64 years with attention deficit hyperactivity disorder or narcolepsy during 2013-2019. RESULTS: We observed the greatest number of treatment episodes for ANDA 040422 (n = 525 771), followed by ANDA 202424 (n = 181 693), ANDA 040439 (n = 62 363), ANDA 040440 (n = 21 143), and ANDA 040480 (n = 8792). Of those with switches away from their original ANDA, episodes initiated on generic products under ANDA 040422 (48.6%) and ANDA 202424 (43.0%) were most likely to switch back, while those initiated on generic product under ANDA 040480 were least likely (24.1%). Of those episodes with switches to a generic under an ANDA of interest, about one-third (range 27.1% to 37.0%) switched back to the same product. These switches back had a median time to switch of about 30 days. CONCLUSIONS: These descriptive analyses, although subject to limitations, did not suggest increased switching away or switching back after use of the generics of interest. Continued post-marketing surveillance is warranted.

Mortality Among Parkinson's Disease Patients Treated With Pimavanserin or Atypical Antipsychotics: An Observational Study in Medicare Beneficiaries.

OBJECTIVE: Pimavanserin, a serotonin 5-HT2 antagonist, is indicated for treatment of hallucinations and delusions associated with Parkinson's disease psychosis. In premarketing trials in patients with Parkinson's disease psychosis, 11% of patients died during open-label pimavanserin treatment. Antipsychotics, which are used off-label in Parkinson's disease psychosis, increase mortality in dementia patients. The authors compared mortality with pimavanserin and atypical antipsychotics in a large database. METHODS: This was a retrospective new-user cohort study of Medicare beneficiaries with Parkinson's disease initiating pimavanserin (N=3,227) or atypical antipsychotics (N=18,442) from April 2016 to March 2019. All-cause mortality hazard ratios and 95% confidence intervals were estimated for pimavanserin compared with atypical antipsychotics, using segmented proportional hazards regression over 1-180 and 181+ days of treatment. Potential confounding was addressed through inverse probability of treatment weighting (IPTW). RESULTS: Pimavanserin users had a mean age of approximately 78 years, and 45% were female. Before IPTW, some comorbidities were more prevalent in atypical antipsychotic users; after IPTW, comorbidities were well balanced between groups. In the first 180 days of treatment, mortality was approximately 35% lower with pimavanserin than with atypical antipsychotics (hazard ratio=0.65, 95% CI=0.53, 0.79), with approximately one excess death per 30 atypical antipsychotic-treated patients; however, during treatment beyond 180 days, there was no additional mortality advantage with pimavanserin (hazard ratio=1.05, 95% CI=0.82, 1.33). Pimavanserin showed no mortality advantage in nursing home patients. CONCLUSIONS: Pimavanserin use was associated with lower mortality than atypical antipsychotic use during the first 180 days of treatment, but only in community-dwelling patients, not nursing home residents.

Does maternal asthma contribute to racial/ethnic disparities in obstetrical and neonatal complications?

PURPOSE: To examine whether maternal asthma contributes to racial/ethnic differences in obstetrical and neonatal complications. METHODS: Data on white (n = 110,603), black (n = 50,284), and Hispanic (n = 38,831) singleton deliveries came from the Consortium on Safe Labor. Multilevel logistic regression models, with an interaction term for asthma and race/ethnicity, estimated within-group adjusted odds ratios (aORs) for gestational diabetes, gestational hypertension, pre-eclampsia, placental abruption, premature rupture of membranes, preterm delivery, maternal hemorrhage, neonatal intensive care unit admissions, small for gestational age, apnea, respiratory distress syndrome, transient tachypnea of the newborn, anemia, and hyperbilirubinemia after adjustment for clinical and demographic confounders. Nonasthmatics of the same racial/ethnic group were the reference group. RESULTS: Compared with nonasthmatics, white asthmatics had increased odds of pre-eclampsia (aOR, 1.28; 95% confidence interval [CI], 1.15-1.43) and maternal hemorrhage (aOR, 1.14; 95% CI, 1.04-1.23). White and Hispanic infants were more likely to have neonatal intensive care unit admissions (aOR, 1.19; 95% CI, 1.11-1.28; aOR, 1.16; 95% CI, 1.02-1.32, respectively) and be small for gestational age (aOR, 1.11; 95% CI, 1.02-1.20; aOR, 1.26; 95% CI, 1.10-1.44, respectively), and Hispanic infants were more likely to have apnea (aOR, 1.32; 95% CI, 1.02-1.69). CONCLUSIONS: Maternal asthma did not affect most obstetrical and neonatal complication risks within racial/ethnic groups. Despite their increased risk for both asthma and many complications, our findings for black women were null. Asthma did not contribute to racial/ethnic disparities in complications.