Uptake of new drugs in the early post-approval period in the Mini-Sentinel distributed database

The Population-level Effect of Adjuvant Therapies on Breast Cancer Recurrence: Application of the Trend-in-Trend Design

PURPOSE

Breast cancer has an average 10-year relative survival reaching 84%. This favorable survival is due, in part, to the introduction of biomarker-guided therapies. We estimated the population-level effect of the introduction of two adjuvant therapies-tamoxifen and trastuzumab-on recurrence using the trend-in-trend pharmacoepidemiologic study design.

METHODS

We ascertained data on women diagnosed with nonmetastatic breast cancer who were registered in the Danish Breast Cancer Group clinical database. We used the trend-in-trend design to estimate the population-level effect of the introduction of (1) tamoxifen for postmenopausal women with estrogen receptor (ER)-positive breast cancer in 1982, (2) tamoxifen for premenopausal women diagnosed with ER-positive breast cancer in 1999, and (3) trastuzumab for women <60 years diagnosed with human epidermal growth factor receptor 2-positive breast cancer in 2007.

RESULTS

For the population-level effect of the introduction of tamoxifen among premenopausal women diagnosed with ER-positive breast cancer in 1999, the risk of recurrence decreased by nearly one-half (OR = 0.52), consistent with evidence from clinical trials; however, the estimate was imprecise (95% confidence interval [CI] = 0.25, 1.85). We observed an imprecise association between tamoxifen use and recurrence from the time it was introduced in 1982 (OR = 1.24 95% CI = 0.46, 5.11), inconsistent with prior knowledge from clinical trials. For the introduction of trastuzumab in 2007, the estimate was also consistent with trial evidence, though imprecise (OR = 0.51; 95% CI = 0.21, 22.4).

CONCLUSIONS

We demonstrated how novel pharmacoepidemiologic analytic designs can be used to evaluate the routine clinical care and effectiveness of therapeutic advancements in a population-based setting while considering some limitations of the approach.

Quantifying the utilization of medical devices necessary to detect postmarket safety differences: A case study of implantable cardioverter defibrillators

PURPOSE

To estimate medical device utilization needed to detect safety differences among implantable cardioverter defibrillators (ICDs) generator models and compare these estimates to utilization in practice.

METHODS

We conducted repeated sample size estimates to calculate the medical device utilization needed, systematically varying device-specific safety event rate ratios and significance levels while maintaining 80% power, testing 3 average adverse event rates (3.9, 6.1, and 12.6 events per 100 person-years) estimated from the American College of Cardiology's 2006 to 2010 National Cardiovascular Data Registry of ICDs. We then compared with actual medical device utilization.

RESULTS

At significance level 0.05 and 80% power, 34% or fewer ICD models accrued sufficient utilization in practice to detect safety differences for rate ratios <1.15 and an average event rate of 12.6 events per 100 person-years. For average event rates of 3.9 and 12.6 events per 100 person-years, 30% and 50% of ICD models, respectively, accrued sufficient utilization for a rate ratio of 1.25, whereas 52% and 67% for a rate ratio of 1.50. Because actual ICD utilization was not uniformly distributed across ICD models, the proportion of individuals receiving any ICD that accrued sufficient utilization in practice was 0% to 21%, 32% to 70%, and 67% to 84% for rate ratios of 1.05, 1.15, and 1.25, respectively, for the range of 3 average adverse event rates.

CONCLUSIONS

Small safety differences among ICD generator models are unlikely to be detected through routine surveillance given current ICD utilization in practice, but large safety differences can be detected for most patients at anticipated average adverse event rates.

The Potential Return on Public Investment in Detecting Adverse Drug Effects

BACKGROUND

Many countries lack fully functional pharmacovigilance programs, and public budgets allocated to pharmacovigilance in industrialized countries remain low due to resource constraints and competing priorities.

OBJECTIVE

Using 3 case examples, we sought to estimate the public health and economic benefits resulting from public investment in active pharmacovigilance programs to detect adverse drug effects.

RESEARCH DESIGN

We assessed 3 examples in which early signals of safety hazards were not adequately recognized, resulting in continued exposure of a large number of patients to these drugs when safer and effective alternative treatments were available. The drug examples studied were rofecoxib, cerivastatin, and troglitazone. Using an individual patient simulation model and the health care system perspective, we estimated the potential costs that could have been averted by early systematic detection of safety hazards through the implementation of active surveillance programs.

RESULTS

We found that earlier drug withdrawal made possible by active safety surveillance would most likely have resulted in savings in direct medical costs of $773-$884 million for rofecoxib, $3-$10 million for cerivastatin, and $38-$63 million for troglitazone in the United States through the prevention of adverse events. By contrast, the yearly public investment in Food and Drug Administration initiated population-based pharmacovigilance activities in the United States is about $42.5 million at present.

CONCLUSION

These examples illustrate a critical and economically justifiable role for active adverse effect surveillance in protecting the health of the public.

Postmarket Safety Events Among Novel Therapeutics Approved by the US Food and Drug Administration Between 2001 and 2010

IMPORTANCE

Postmarket safety events of novel pharmaceuticals and biologics occur when new safety risks are identified after initial regulatory approval of these therapeutics. These safety events can change how novel therapeutics are used in clinical practice and inform patient and clinician decision making.

OBJECTIVES

To characterize the frequency of postmarket safety events among novel therapeutics approved by the US Food and Drug Administration (FDA), and to examine whether any novel therapeutic characteristics known at the time of FDA approval were associated with increased risk.

DESIGN AND SETTING

Cohort study of all novel therapeutics approved by the FDA between January 1, 2001, and December 31, 2010, followed up through February 28, 2017.

EXPOSURES

Novel therapeutic characteristics known at the time of FDA approval, including drug class, therapeutic area, priority review, accelerated approval, orphan status, near-regulatory deadline approval, and regulatory review time.

MAIN OUTCOMES AND MEASURES

A composite of (1) withdrawals due to safety concerns, (2) FDA issuance of incremental boxed warnings added in the postmarket period, and (3) FDA issuance of safety communications.

RESULTS

From 2001 through 2010, the FDA approved 222 novel therapeutics (183 pharmaceuticals and 39 biologics). There were 123 new postmarket safety events (3 withdrawals, 61 boxed warnings, and 59 safety communications) during a median follow-up period of 11.7 years (interquartile range [IQR], 8.7-13.8 years), affecting 71 (32.0%) of the novel therapeutics. The median time from approval to first postmarket safety event was 4.2 years (IQR, 2.5-6.0 years), and the proportion of novel therapeutics affected by a postmarket safety event at 10 years was 30.8% (95% CI, 25.1%-37.5%). In multivariable analysis, postmarket safety events were statistically significantly more frequent among biologics (incidence rate ratio [IRR] = 1.93; 95% CI, 1.06-3.52; P = .03), therapeutics indicated for the treatment of psychiatric disease (IRR = 3.78; 95% CI, 1.77-8.06; P < .001), those receiving accelerated approval (IRR = 2.20; 95% CI, 1.15-4.21; P = .02), and those with near-regulatory deadline approval (IRR = 1.90; 95% CI, 1.19-3.05; P = .008); events were statistically significantly less frequent among those with regulatory review times less than 200 days (IRR = 0.46; 95% CI, 0.24-0.87; P = .02).

CONCLUSIONS AND RELEVANCE

Among 222 novel therapeutics approved by the FDA from 2001 through 2010, 32% were affected by a postmarket safety event. Biologics, psychiatric therapeutics, and accelerated and near-regulatory deadline approval were statistically significantly associated with higher rates of events, highlighting the need for continuous monitoring of the safety of novel therapeutics throughout their life cycle.