Effective and affordable treatments are key to tackling both the UK’s burgeoning diabetes crisis and the financial challenges facing the NHS. However, the success of generics and biosimilars depends to a considerable degree on the work of laboratories, emphasises Elena Wolff-Holz.

The United Kingdom faces a diabetes challenge that is no longer emerging but firmly established. More than 5.8 million people are currently living with diabetes in the UK, including both diagnosed and undiagnosed cases, and millions more are at increased risk due to obesity, physical inactivity and Credit: Sweet Life Bringing best value wider socioeconomic determinants of health. Obesity prevalence continues to rise, contributing to earlier onset of type 2 diabetes, increasing insulin resistance and a growing burden of cardiovascular and renal disease.

This represents not only a clinical challenge but also a long-term sustainability challenge for the NHS. Approximately 60% of NHS expenditure on diabetes is currently directed toward potentially preventable complications such as cardiovascular events, kidney failure requiring dialysis, amputations and vision loss, rather than routine care and medicines. To alter this trajectory, the UK must act on two complementary priorities: earlier and more accurate diagnosis, and broader access to effective and affordable treatments.

Biosimilar insulins and generic versions of GLP-1s may help expand treatment options while supporting the financial sustainability of the NHS. Their use should be guided by the relevant regulatory status, clinical evidence and local and national guidance.

However, medicines alone do not deliver positive outcomes. Their clinical and economic value also depends on decisions taken upstream, particularly with laboratory diagnostics. Laboratory professionals play a central role in translating diagnostic and therapeutic innovation into safe, effective and sustainable real-world care.

Diagnosis: where access begins or fails

Laboratories underpin diabetes diagnosis through established biochemical criteria. In clinical practice, diabetes may be diagnosed using an HbA1c value of at least 48 mmol/ mol (6.5%), a fasting plasma glucose of at least 7.0 mmol/L, or a two-hour plasma glucose of at least 11.1 mmol/L during an oral glucose tolerance test. While these thresholds are well defined, their reliability depends on standardised assays, appropriate quality control and adherence to nationally and internationally recognised reference systems.

Beyond diagnosis, laboratory data is essential for accurate diabetes classification, which directly informs treatment choice. Type 1 diabetes is typically associated with hyperglycaemia alongside low or absent C-peptide and the presence of pancreatic islet autoantibodies such as GAD, IA 2, or ZnT8.

Medicines alone do not deliver positive outcomes. Their clinical and economic value also depends on decisions taken upstream, particularly with laboratory diagnostics

Type 2 diabetes more commonly presents with preserved C peptide and features of insulin resistance. Other forms including monogenic diabetes, pancreatogenic diabetes, drug induced hyperglycaemia and gestational diabetes require additional laboratory input to ensure correct identification.

Misclassification carries real clinical risk. Treating type 1 diabetes as type 2 can delay necessary insulin therapy and increase the risk of diabetic ketoacidosis. Conversely, early or inappropriate insulin use in insulin resistant type 2 diabetes may increase the risk of weight gain and hypoglycaemia, undermining adherence and long-term outcomes.

Stratification: matching therapy to patient need

Laboratory professionals do far more than establish a diagnosis; they support stratification to inform treatment decisions. Baseline HbA1c provides an objective measure of disease severity, while patterns of fasting versus post prandial hyperglycaemia can help inform the therapeutic approach.

Cardiometabolic risk stratification is equally important. Routine laboratory assessments, including lipid profiles, estimated glomerular filtration rate (eGFR), urine albumin to creatinine ratio, and liver enzymes, identify patients at elevated cardiovascular or renal risk. In relevant patient populations and in line with licensed indications and applicable guidance, GLP-1 receptor agonist-based therapies have demonstrated benefits on glycaemic control and weight, with cardiovascular outcome data available for some agents.

Measures related to obesity and insulin resistance, such as BMI and waist circumference, interpreted alongside laboratory findings, further refine treatment decisions.

This precision matters. Biosimilar insulins and generic GLP-1 therapies should be considered in line with individual clinical need, the licensed indication and applicable guidance.

The cost of late or inaccurate diagnosis

When diagnosis is delayed or incorrect, patients bear the immediate consequences. Prolonged uncontrolled hyperglycaemia accelerates vascular damage, increasing the risk of cardiovascular disease, kidney failure, neuropathy, visual impairment and acute metabolic emergencies such as diabetic ketoacidosis or hyperosmolar hyperglycaemic states. Quality of life deteriorates, care becomes progressively more complex and mortality increases.

Beyond diagnosis, laboratory data is essential for accurate diabetes classification, which directly informs treatment choice

The NHS also bears the cost of late diagnosis as it shifts resources away from relatively low cost prevention and early treatment toward expensive emergency care, hospital admissions, dialysis, rehabilitation and long-term social support. Without diagnostic precision, the financial benefits achieved through biosimilar insulins or generic GLP-1 therapies risk being offset by avoidable downstream complications.

Laboratories shape outcomes beyond treatment initiation

The role of the laboratory continues long after therapy is initiated. Regular monitoring of HbA1c and fasting plasma glucose supports safe dose titration, confirms treatment effectiveness and helps clinicians and patients avoid therapeutic inertia.

Laboratory results also identify co-existing conditions that influence treatment choice and safety. Reduced renal function may necessitate careful insulin titration or influence GLP-1 dosing decisions. Elevated liver enzymes and triglycerides may signal non-alcoholic fatty liver disease and insulin resistance, which are associated with a favourable metabolic response to GLP-1-based therapies. Anaemia, renal impairment and advanced age increase hypoglycaemia risk and may prompt simpler treatment regimens and closer monitoring.

Laboratory-driven assessment helps manage treatment complexity by identifying individuals at higher risk of adverse outcomes and enabling personalised rather than uniform treatment approaches.

Building confidence in biosimilars and generics

Appropriate clinical confidence is important for the use of biosimilar insulins and generic GLP-1 therapies where relevant. Robust laboratory monitoring can support clinical decision-making by providing objective evidence of patient outcomes.

Consistent HbA1c trends, stable glucose control and appropriate safety markers can help inform whether treatment is performing as expected in routine practice.

The importance of standardisation

All of this depends on validated and standardised testing methodology. HbA1c measurement in the UK is traceable to IFCC reference methods, ensuring consistency across laboratories. Plasma glucose, lipid parameters and creatinine are similarly calibrated against international reference standards. Accreditation frameworks such as ISO 15189 require documented quality systems, staff competency and regular audits, supporting reliability across sites and platforms.

Without such standardisation, analytical variation could be misinterpreted as treatment failure, either at treatment initiation or following a therapy switch, potentially leading to unnecessary changes in care.

Real-world evidence: from policy to practice

As biosimilar insulins and generic GLP-1 receptor agonists are used across large and diverse populations, laboratory-generated real-world data can provide useful supportive evidence.

Without diagnostic precision, the financial benefits achieved through biosimilar insulins or generic GLP-1 therapies risk being offset by avoidable downstream complications

Aggregated laboratory outcomes may help inform understanding of how regulatory assessments and clinical evidence translate into routine care across different patient groups and healthcare settings.

At a system level, this reinforces that affordability and clinical quality are complementary rather than competing outcomes.

Laboratories: a vital partner in diabetes care

The UK’s diabetes challenge will not be addressed by therapeutic measures alone. It will be shaped by precision in diagnosis, classification, stratification, monitoring and evaluation of effectiveness. Biosimilar insulins and generic GLP-1 receptor agonists can meaningfully expand access and improve outcomes, but only when laboratories are recognised as strategic partners in diabetes care.

Thus, laboratories are not simply a supporting function in the diabetes pathway. Long-term investment in diagnostic quality, assay standardisation and laboratory-driven evidence will be essential to converting therapeutic innovation into better health outcomes and supporting a more financially sustainable NHS.

• Dr Elena Wolff- Holz is chief medical officer at Biocon Biologics

References:

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