Professor Saad Shakir, director of the Drug Safety Research Unit looks at observational research in the UK and why it's one of the nation's core strengths.
The role of observational research, carried out after drugs have been approved for use in the general population, has come to the fore in the wake of Covid-19, when new vaccines and treatments needed to be fast-tracked through research and development to save lives.
While clinical trials are considered the gold standard for evaluating the efficacy of medicines and vaccines, they do have limitations.
They tend to include healthy, young participants, and very few, if any, older people, pregnant women, those with co-morbidities or people taking several other medicines. Often clinical trials exclude the very patient groups likely to benefit the most from the new drug. Or in some cases, the excluded groups are the ones more likely to experience adverse drug reactions.
In addition, while clinical trials can include large cohorts, they simply can’t offer the sheer scale required to accurately reflect real-world use.
This is no criticism of our excellent research set-up and the key role for clinical trials in understanding if and how medicines and vaccines work. But Covid-19 has shone on light on the entire research process.
Evidence from post-authorisation observational studies helps us understand the effectiveness and safety of medicines and vaccines in the real world. They are not in competition with clinical trials. They complement them.
While observational studies have always been mandated in drug development, their value is becoming more widely recognised now.
In particular, UK observational studies are getting noticed. And with good reason.
Our NHS system allows for longitudinal follow-ups that simply aren’t possible in many other countries. UK patients are usually assigned their own GP, and their medical record moves with them if they change practice. This single medical record for each person from cradle to grave provides a more complete picture for researchers to study than other nations’ records allow.
Our NHS records also enable a range of observational study designs, for example where researchers study a period of exposure to a particular medicine and compare it with a control period of non-exposure in the same patient to establish any changes in the risk of adverse side effects.
The detail of our medical records is also an advantage for observational researchers. Information on demographics, prescribed medications, vaccine history, health screening, diagnosed conditions and potential confounders, such as body mass index and ethnicity, are all logged in detail in our records.
All this information is available to researchers, anonymised, of course, and subject to the right approvals. Initiatives such as the Clinical Practice Research Datalink (CPRD), The Health Improvement Network (THIN) and OpenSAFELY support UK, European and international studies. It’s also possible to link to other databases, including hospital admissions and ONS death data.
DSRU researchers have worked with these excellent data sources for many years, and our research findings on a broad range of medicines used by UK patients are read by global pharmaceutical clients, regulatory bodies and other academics around the world.
Right now, we’re conducting several observational studies into the safety of all Covid-19 vaccines available in the UK. We are also monitoring this year’s annual flu vaccine in children, as we have done every year since 2014, to mention just a few.
Covid-19 has certainly prompted greater attention in our field, and in our patch. And we’re proud to be a significant player. But ultimately, it’s our unique NHS system that puts the UK centre stage when it comes to observational research.