Effectiveness of risk minimization measures for valproate: a drug utilization study based on implementation of a risk minimization programme in Europe, analysis of data from the UK

OBJECTIVE

Since 2014, valproate has not been recommended for use in girls and women of childbearing potential unless other treatments are ineffective or not tolerated. Risk minimization measures (RMMs) of valproate were implemented to reduce the potential risks of developmental disorders among pregnant women. A drug utilization study was carried out to assess the effectiveness of RMMs.

METHODS

This was a multinational, non-interventional cohort study. For the UK, existing data from the Clinical Practice Research Datalink database were used. The primary study endpoint was a change in the proportion of valproate initiations preceded by other medications relevant for valproate indications before and after implementation of RMMs.

RESULTS

The proportion of valproate initiations preceded by medications related to valproate indications increased after RMM implementation in incident female users in the UK from 66.4% to 72.4%. The proportion of incident prescriptions for epilepsy and bipolar disorder with prior medication related to valproate indications increased, from 36.2% to 44.1% and 72.9% to 77.8%, respectively. The incidence rate of valproate-exposed pregnancies decreased from 16.9 to 10.9 per 1000 person-years in the pre- and post-implementation periods, respectively.

CONCLUSIONS

Results from this study indicated some improvement in physician prescribing and a potential reduction in valproate-exposed pregnancies in the UK. Given only modest improvement has been achieved, additional RMMs were implemented in 2018.

Comparison of text processing methods in social media-based signal detection

PURPOSE

Adverse event (AE) identification in social media (SM) can be performed using various types of natural language processing (NLP) and machine learning (ML). These methods can be categorized by complexity and precision level. Co-occurrence-based ML methods are rather basic, as they identify simultaneous appearance of drugs and clinical events in a single post. In contrast, statistical learning methods involve more complex NLP and identify drugs, events, and associations between them. We aimed to compare the ability of co-occurrence and NLP to identify AEs and signals of disproportionate reporting (SDR) in patient-generated SM. We also examined the performance of lift in SM-based signal detection (SD).

METHODS

Our examination was performed in a corpus of SM posts crawled from open online patient forums and communities, using the spontaneously reported VigiBase data as reference data set.

RESULTS

We found that co-occurrence and NLP produce AEs, which are 57% and 93% consistent with VigiBase AEs, respectively. Among the SDRs identified both in SM and in VigiBase, up to 55.3% were identified earlier in co-occurrence, and up to 32.1% were identified earlier in NLP-processed SM. Using lift in SM SD provided performance similar to frequentist methods, both in co-occurrence and in NLP-processed AEs.

CONCLUSION

Our results indicate that using SM as a data source complementary to traditional pharmacovigilance sources should be considered further. Various levels of SM processing may be considered, depending on the preferred policies and tolerance for false-positive to false-negative balance in routine pharmacovigilance processes.

Reinterventions in the superficial femoral artery

The management of peripheral arterial disease (PAD) has drastically changed since the introduction and advancement of endovascular surgery. The majority of PAD that requires mechanical treatment is managed with endovascular interventions using a variety of techniques and devices. The infrainguinal vasculature, especially the superficial femoral artery (SFA), poses a significant challenge to successful long-term outcomes for a variety of reasons. Because some of these procedures have limited longevity, the management of patients that require reintervention is worthy of special consideration and strategic discussion. This article reviews the risks and failure modes of SFA interventions and the treatment options and techniques for reinterventions.

A case of angiocentric T-cell lymphoma presenting as lethal midline granuloma

A case of angiocentric T-cell lymphoma with glabellar skin being the only affected site was reported. A 43-year-old woman had a several months' history of glabellar swelling followed by progressive and destructive ulceration of the region. Histopathology of the biopsied specimen showed panniculitis with atypical lymphocytes and degenerative vessels filled with atypical cells. Most of the infiltrated lymphocytes were positive for CD2, CD3, CD4 and CD5. Antibodies to Epstein-Barr virus were detected in the patient serum. Intensive chemotherapy using a protocol of the L17M regimen was partially effective for clinical manifestations. Angiocentric T-cell lymphoma presenting as lethal midline granuloma is a rare but distinct entity with an acute fatal course.