How DNA-Driven Prescriptions Could Save the NHS over £530M Annually

Using DNA-Driven Prescriptions to Prevent 15% of Hospital Admissions

Every year, adverse drug reactions (ADRs) account for 6.5% of hospital admissions in the UK, costing the NHS an estimated £530 million annually.

• Landmark studies in the UK in 2004 found ADRs to be related to 6.5% of hospital admissions. More recent systematic reviews have reported figures of up to 15.6%.
• Previous cost analyses of medication-related harm in England provide annual estimates of £1.9 billion: £529 million for potentially avoidable ADR-related admissions and £396 million for discharged elderly people.

These preventable incidents burden an already overstretched healthcare system and impact patients' lives with prolonged recovery times and unnecessary suffering.

But, what if there were a way to eliminate this trial-and-error approach to prescribing? Enter pharmacogenomics: the future of personalised medicine.

Much like how allergy tests help people avoid triggers, DNA-driven prescriptions use your genetic makeup to ensure the medications you take are safe and effective.

For instance, certain painkillers like codeine (opioid pain-relief medicine used for the short-term relief of mild to moderate pain) are metabolised by the CYP2D6 gene. Individuals with a genetic variation in CYP2D6 may metabolise the drug too quickly, rendering it ineffective, or too slowly, leading to accumulation in their plasma to toxic levels.

This revolutionary approach is already being used in targeted treatments for cancer and HIV.

Experts believe its widespread adoption could transform healthcare in the UK, saving lives and significant NHS resources (Source).

The Problem: Adverse Drug Reactions

Adverse drug reactions affect thousands of patients annually, leading to unnecessary hospitalizations and severe health complications. According to a study published in the British Medical Journal, ADRs account for 6.5% to 15% of hospital admissions, making them a significant public health issue.

Additionally, the research in BMJ Open highlights the potential of DNA-based testing to mitigate this issue by tailoring medication prescriptions according to pharmacogenetic guidelines, optimising drug efficacy and reducing the risk of adverse reactions.

These incidents also place a financial strain on the NHS, which spends over £530 million yearly addressing ADR-related admissions.

Why do ADRs happen? Many are caused by genetic differences in how patients metabolise drugs. Variations in genes like CYP2D6 or CYP2C19 mean that a medication that works for one person could cause harmful side effects in another.

For example, clopidogrel, a common blood thinner, requires activation by the CYP2C19 gene. Patients with certain genetic variants in CYP2C19 (c.681G>A; rs4244285) may not process clopidogrel effectively, leading to increased risk for serious adverse cardiovascular events (~25 - 50% of the population).

Currently, these genetic factors are not routinely considered when prescribing medications, leaving patients vulnerable to ineffective or dangerous side effects.

A Solution: DNA-Driven Prescriptions

Pharmacogenomics is the study of how genes affect a person’s response to drugs. By analysing a patient’s genetic profile, healthcare providers can tailor prescriptions to ensure optimal effectiveness while minimising risks.

Current Applications

Pharmacogenomic testing is already used for:

Cancer Treatments: Ensuring only patients with HER2-positive breast cancer receive trastuzumab (Herceptin)

• Studies show that targeted therapies, such as trastuzumab, have significantly improved outcomes for patients with HER2-positive breast cancer. According to a review of pharmacogenetic applications, targeted treatments for HER2-positive cancers leverage genetic biomarkers to personalize therapy, enhancing efficacy and reducing adverse effects compared to non-targeted treatments.

HIV Medications: Preventing severe reactions to abacavir

• Pharmacogenomic testing has been instrumental in preventing severe hypersensitivity reactions to abacavir by screening for the HLA-B*57:01 gene variant.
• This pre-treatment test ensures that patients at risk of life-threatening reactions are identified and alternative therapies are used, highlighting the value of personalised medicine.

Anticoagulants: Preventing bleed complications

• Adjusting warfarin doses based on CYP2C9 and VKORC1 gene variants to prevent bleeding complications.
• These successes demonstrate that DNA-driven prescriptions are not just theoretical but already improving patient outcomes.

Lifelong Benefits

A single preemptive pharmacogenomic test can provide insights for a lifetime of treatment decisions. Much like knowing your allergies helps you avoid certain foods or environments, knowing your genetic profile helps you avoid ineffective or harmful medications.

The Opportunity for the NHS

Adopting pharmacogenomics across the NHS could revolutionise healthcare in the UK. Adverse drug reactions currently account for 6.5% to 15% of all hospital admissions, costing the NHS over £530 million annually. Addressing this issue with pharmacogenomics testing is particularly crucial as the NHS faces ongoing resource constraints and funding shortages. 

With rising demands on healthcare services, implementing pharmacogenomics could reduce the financial and operational strain on the NHS, freeing up resources for other critical areas. This figure doesn’t even account for additional savings from fewer ineffective prescriptions and shorter hospital stays.

Aligning with NHS Goals

The NHS has already committed to advancing precision medicine through its Genomic Medicine Service, which integrates genomic technology to improve population health. For example:

• The NHS Genomic Medicine Service provides genomic testing to patients undergoing fluoropyrimidine-based chemotherapy, identifying DPYD gene variants to reduce the risk of severe toxicity. 
• Approximately 38,000 patients are initiated on fluoropyrimidine-based therapy each year in England. The NHS Genomic Laboratory Hubs (GLHs) process around 3,100 samples monthly for DPYD testing, with referrals from 115 hospitals across England.

This aligns with the NHS Long Term Plan's goals of improving patient safety and operational efficiency. 

• Past initiatives, such as the 100,000 Genomes Project, have laid the foundation for integrating genomics into routine clinical care. This landmark program, which sequenced the genomes of 100,000 patients with rare diseases and cancer, demonstrated the transformative potential of precision medicine and directly contributed to the establishment of the NHS Genomic Medicine Service (NHS England).

A Healthier UK

By preventing ADRs, pharmacogenomics ensures patients recover faster, spend less time in hospitals, and lead healthier, more productive lives. This benefits not only individuals but also the economy, as fewer workdays are lost to illness.

Overcoming Challenges

Barriers to Adoption

Despite its promise, pharmacogenomics faces several barriers in the UK:

• Infrastructure Gaps: Limited access to genomic testing facilities.
• Professional Awareness: Many healthcare providers are not yet trained in pharmacogenomics.
• Public Awareness: Most patients are unfamiliar with the concept and its benefits.

Steps Forward

To unlock the potential of pharmacogenomics, the NHS and private sectors must:

1. Invest in testing infrastructure and training programs.
2. Launch public education campaigns to raise awareness.
3. Collaborate with global leaders like the US and Denmark, where pharmacogenomics is already mainstream.
   
   

Global Comparisons

Countries like the US and Denmark are leading the way in integrating pharmacogenomics into healthcare. 

Denmark has implemented nationwide testing for thiopurine methyltransferase (TPMT) genotyping, while France has integrated this approach into its healthcare system. Both initiatives aim to reduce the risk of severe toxicity in patients receiving thiopurine-based treatments, particularly for leukemia and autoimmune diseases. (Source)

Pharmacogenomic protocols have increasingly been integrated into cancer treatments in the U.S., highlighting the scalability and efficacy of DNA-driven prescriptions. These advancements have enabled more precise therapies tailored to the genetic profiles of patients, improving outcomes and reducing adverse effects. PMC.

In Canada, pharmacogenomic testing has been utilised to assess variations in the TPMT and NUDT15 genes among pediatric patients with inflammatory bowel disease. This approach helps in tailoring thiopurine therapy to individual genetic profiles, thereby minimising adverse drug reactions and optimising treatment efficacy. Oxford Academic. 

These examples show that widespread adoption is not only feasible but also highly beneficial.

Conclusion

By investing in pharmacogenomics, the UK has the opportunity to transform its healthcare system. DNA-driven prescriptions offer a solution that saves lives, reduces NHS costs, and improves patient outcomes. Much like allergy tests became a healthcare staple, pharmacogenomics could soon be an essential tool in every doctor’s arsenal.

The NHS and healthcare providers must prioritise pharmacogenomics to ensure it becomes a standard part of patient care. With a single test, we can unlock a lifetime of better medicine, smarter spending, and healthier lives.

Fact-Checked by Prince Agyirey-Kwakye

This article has been reviewed and fact-checked by Prince Agyirey-Kwakye, Chief Scientific Officer, The AttoGroup, and Laboratory Director at AttoDiagnostics. Prince has over 16 years experience in the NHS with the last 10 years focussed on research and the application of genomic medicine to improve patient outcome. His expert review ensures the accuracy and reliability of the information presented.

Explore PGx Testing