The progressive nature of type 2 diabetes requires frequent intensification of therapy as the disease advances. Unfortunatelly, majority of patients fail to reach HbA1C targets. Clinical inertia is an important contributing factor. On the other side, patients with diabetes frequently have several comorbidities which require therapy as well. Fixed combination therapy can improve compliance and adherence and consequently can improve glycemic control. Combination of metformin and sulfonilurea was on the market for many years. Last few years combination of metformin and DPP-4 inhibitors, metformin and pioglitazone, pioglitazone and SGLT-2 inhibitors, metformin and SGLT-2 inhibitors, SGLT-2 inhibitors and DPP-4 inhibitors and basal insulin and GLP-1 receptor agonist are available in treatment of type 2 diabetes. Their complementary effect on glucoregulation can improve HbA1c significantly. However, there are several limitation of fixed combination therapy, especially in fixed combination of basal insulin and GLP-1 receptor agonists. Fixed combination therapies have limited flexibility, especially in choosing appropriate dose of each drug component what is especially emphasized in fixed combination of basal insulin and GLP-1 receptor agonists.
Increasing dose steps of fixed dose of GLP-1 RA and basal insulin can be limited by risk of hypoglycaemia. Therefore, patients will not be able to receive recommended dose of GLP-1 RA what can consequently require more insulin and can cause weight gain. Treatment decisions should be timely and based on evidence-based guidelines that are tailored to individual patient preferences, prognoses, and co-morbidities. All international and national guidelines emphasize importance of individual approach. However, fixed combinations has to be evaluated separately with respect to an improvement in clinical endpoints and adverse effects. As cost of diabetes is important part of every county's health care budget, it is very important is to take into account the cost of fixed combinations compares to cost of each component.