Worldwide reporting of fatal outcomes after ticagrelor to the US Food and Drug Administration

Mortality and adverse events with brand and generic clopidogrel in the US Food and Drug Administration Adverse Event Reporting System

Aims

Clopidogrel is commonly used even after expiring patents. The brand clopidogrel (BC) was dealt by single company, while numerous manufacturers produce generic clopidogrel (GC). There are no convincing data to compare the safety of different formulations. Therefore, the data yielded from international, uniform, government-mandated registries may be useful.

Methods and results

We assessed primary causative adverse events (PCAE) after BC and GC in the US Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS). The outcomes were divided into death, cardiac, thrombotic/embolic, haemorrhagic, and rash/dermal complications. These primary endpoints were then examined by proportional reporting ratios (PRR) and chi-square (χ2). Among total FAERS (n = 9 466 679) reports, overall BC (n = 88 863) cases were more common than after GC (n = 36 559). When triaged by PCAE role, BC (n = 18 328) was also more abundant than GC (n = 3987). The reported death rates were more than doubled after BC [18.4% vs. 7.0%; PRR = 0.38; 95% confidence interval (95% CI) 0.32–0.43; χ2=369.7; P<0.0001] for total FAERS, and consistent for late 2010–2017 (17.6% vs. 7.0% PRR = 0.40; 95% CI 0.37–0.45; χ2=286.2; P<0.004) PCAE cases. In contrast, GC trended to co-report more cardiac (14.6% vs. 13.3%; PRR = 1.12; 95% CI 1.0–1.25; χ2=3.5; P<0.06). The haemorrhagic (40.9% vs. 32.3%; PRR = 1.45; 95% CI 1.33–1.57; χ2=75.8; P<0.0001), and rash/dermal (5.4% vs. 4.6%; PRR = 1.20; 95% CI 1.0–1.44; χ2=3.75; P<0.05) events were also more common for GC. Thrombotic/embolic events were reported equally (at 7.0%) after each formulation.

Conclusion

The PCAE profiles differ with BC and GC in FAERS. While deaths reports were higher, the rates of cardiac, haemorrhagic, and skin complications were less common for BC. Despite expected reporting bias, this may indicate that the manufacturers of GC are reluctant to report deaths to the FDA. However, the overall adverse event profile suggests potentially better safety of BC over GC formulations.

Assessing Cancer Signal during Oral Antiplatelet Therapy in the Food and Drug Administration Adverse Event Reporting System: Mission Impossible

Whether aggressive prolonged dual antiplatelet therapy (DAPT) promotes solid cancer risks remains a critical unsolved issue. Since the evidence from randomized trials, affiliated U.S. Food and Drug Administration (FDA) reviews, meta-analyses, and national registries is mixed, the search is ongoing. The FDA Adverse Event Reporting System (FAERS) is a global passive surveillance repository requiring mandatory updates for serious events. We assessed the frequencies of co-reporting any cancers with oral antiplatelet agent (OAA) strategies in FAERS. We examined the entire FAERS database ( n  = 8,604,889) with regard to monotherapy or DAPT with OAA, suspected causative role, and co-reporting any cancers ( n  = 433,111). We extracted cancer cases during monotherapy with aspirin (20,984 out of 462,371 or 4.54%), clopidogrel (2,797 out of 62,791 or 4.45%), prasugrel (119 out of 4,364 or 2.73%), and ticagrelor (144 out of 8.268 or 1.71%). DAPT with clopidogrel reported (2,453 out of 58,101, or 4.22%); prasugrel (162 out of 4,036, or 4.01%); and ticagrelor (195 out of 5,302 or 3.68%) cancer reports all on top of aspirin. We conclude that FAERS is currently unreliable for adequate assessment of cancer risks during DAPT. The retrieved evidence appears random and sporadic, while associated cancers are heavily underreported or/and missed. Without stricter rules, better surveillance, and enforcements, oncology outcome research options in FAERS are challenging.

Aspirin in the Food and Drug Administration Adverse Event Reporting System: Missing Demographics and Underreporting

Background  The U.S. Food and Drug Administration (FDA) Adverse Event (AE) Reporting System (FAERS) is a global passive surveillance repository requiring mandatory updates by pharmaceutical manufacturers. Oral antiplatelet agents (OAAs) including aspirin (acetylsalicylic acid [ASA]) are broadly used to prevent thrombosis, at the expense of extra bleeding risks. However, the OAA filing quality and their comparative patterns in FAERS are unknown. We assessed completeness of original annual FAERS reports for OAA with special attention on ASA. Methods  We extracted AE cases co-reported with OAA including ASA, clopidogrel, prasugrel, ticagrelor, vorapaxar, or their combination. The 2015 FAERS cases were examined based on OAA distribution, suspected causative role, missing gender or age, and most common AEs after ASA. Results  A total of 1,187,729 reports qualified the inclusion criteria. The majority ( n  = 1,121,989) of the reports contain no reference of OAA, while 65,730 reports contain reference of at least one OAA, including 47,900 ASA cases. Therapy with ASA was heavily (>50%) underreported when used with prasugrel or ticagrelor, but still dominant (72.8%) among OAAs, followed by clopidogrel (18.7%), prasugrel (4.1%), ticagrelor (3.6%), and anecdotal vorapaxar (0.05%). Despite current recommendations, some (0.73%) reports contain multi-OAAs. The primary role of ASA in AE reporting was seldom (<1%), followed by clopidogrel (2.9%), prasugrel (3.7%), and highest for ticagrelor (9.3%). Missing gender after OAA was not common (<10%), but age was missing in approximately 25% of reports. Bleeding was the most frequent AE associated with ASA. Conclusion  The quality of reporting for OAA in general and ASA in particular can be improved by stricter FDA rules, better surveillance, and enforcements. Heavy ASA underreporting during dual antiplatelet therapy and missed demographic variables challenge outcome research capacities for establishing drug interactions in FAERS.