Special Section: Pharmacovigilance

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Using Community Reporters as a Strategic Source for Evaluating Vaccine Effectiveness
Nancy A. Dreyer
Matthew W. Reynolds

IQVIA Real World Solutions

OVID-19 has highlighted the need for new methods of pharmacovigilance. During the pandemic, people stayed home as much as possible, avoiding public gatherings, delaying going to the doctor for routine medical care, and even holding off seeking medical care for COVID symptoms. This situation was further complicated by social media reports encouraging use of medications outside of their labeled indications, as well as anxiety about using vaccines that were developed quickly and first authorized under emergency use authorization.

This lack of contact with medical care providers interfered with a mainstay of traditional pharmacovigilance safety reporting, namely a knowledgeable reporter (generally the clinician) coming in contact with a patient, identifying potential adverse events (including lack of drug effectiveness), and assessing causality of exposures. In this circumstance, it is desirable to find a way to gather the safety and effectiveness experience with medical products directly from the patient. Of note: In contrast to most drug safety reporting, drug ineffectiveness historically has been driven primarily by direct consumer reports to manufacturers and is the most commonly reported adverse event (AE) in the US FDA Adverse Event Reporting System (FAERS). However, those spontaneous reports from consumers lack the consistency and completeness of information required that would prompt a reviewer to consider further action, as needed.

Here we describe use of a novel, direct-to-patient registry focused on systematic collection of data on lack of effectiveness: in this situation, a case of illness in which a vaccinated individual becomes sick from the same illness that the vaccine is meant to prevent. In this pandemic study, we invited non-medically trained reporters to obtain systematic information on vaccine effectiveness and to contextualize the nature and severity of COVID-19 infections that occurred after COVID-19 vaccination (also known as breakthrough infections). We used social media to reach out for volunteer reporters in the US following a pharmacovigilance model first tested in collaboration with the European Medicines Association.

These unpaid community-based volunteers reported COVID-19 test results, COVID-19 symptoms, and/or COVID-19 vaccination (Pfizer, Moderna, or Johnson & Johnson [J&J]) to an online registry. We did not require participants to upload their vaccine card or test results, but asked about vaccine manufacturer, date, and batch number, and COVID test result and type of test. We regularly review the data, flagging out-of-range responses and improbable clinical combinations (e.g., pregnant males) most likely entered in error. We used these curated data to examine COVID-19 infections including long COVID, and the symptoms reported by people who had received vaccines. The study population was described for three groups—those who were:

  1. fully vaccinated,
  2. partially vaccinated (only received the first dose of a two-dose vaccine or were less than 14 days after their final dose, the time period required to achieve full immunogenic response), or
  3. unvaccinated.

More than 8,000 fully or partially vaccinated volunteers reported their experience, with only one percent reporting a breakthrough infection after full vaccination.

The important take-away from this work is that person-generated health data, also known as patient-reported outcomes, can be a valuable source of information to evaluate vaccine effectiveness. We show that unpaid community-based volunteers are willing to report their vaccine injection date, the vaccine manufacturer, and the extent to which the vaccines were effective. We also used these data to examine what participants perceived to be side effects, which supported comparative side effects analyses among vaccine manufacturers.

Hopefully this type of information will have clinical and social value in that it might help mitigate vaccine hesitancy. Patient registries that can be launched quickly to examine urgent, unmet needs, like this one, provide a novel approach to evaluating the effectiveness of vaccines and generating reliable results before the more formal post-marketing vaccine safety surveillance commitments have been completed.

References available upon request.

A manuscript describing the full results and detailed methodology of this study has been submitted for peer review.