Efficacy and safety of insulin-GLP-1 receptor agonists combination in type 2 diabetes mellitus: a systematic review

ABSTRACT

Introduction: Attaining optimal glycemic targets in patients with type 2 diabetes is often hard and compromised by the shortcomings of the several treatments.

Areas covered: When glycemic levels are not adequately controlled, an association of GLP-1 receptor agonists and insulin therapy can be adopted. In order to assess the benefit/risk profile of this combination therapy, a literature search of randomized clinical trials was performed.Eighteen trials matched the inclusion criteria. In 10 studies, GLP-1 receptor agonists were added on to an existing regimen, whereas insulin added to an existing GLP-1 receptor agonists regimen occurred in 2 studies. Six studies compared GLP-1 receptor agonists with short acting insulin as a treatment strategy to intensify basal insulin therapy.

Expert opinion: Clinical trials herein reviewed demonstrated the safety and the efficacy of combining GLP-1 receptor agonists with basal insulin, with most studies showing equal or slightly superior efficacy, as compared with the addition of prandial insulin, associated with weight loss and less hypoglycemia.

KEYWORDS:

• GLP-1 RA insulin combination
• HbA1c levels
• hypoglycemia
• type 2 diabetes mellitus

Article highlights

• GLP-1 RAs and insulin act by complementary modes of action, exerting potential benefits on weight and reduction of hypoglycemia.

• Several clinical trials herein reviewed showed efficacy and safety of the combination therapy GLP-1RAs – insulin in the treatment of type 2 diabetes.

• GLP-1 RA added to a pre-existing basal insulin therapy is the most common option emerged in clinical trials. This therapeutic strategy allows to reduce the progressive need of insulin doses and promotes a better compliance of the patients.

• Longer studies are needed to assess the long-term efficacy and tolerability of this combination before it can be favored as standard of care for patients with type 2 diabetes failing basal insulin therapy.

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Declaration of interest

The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Additional information

Funding

This paper is part of a supplemental issue funded by the Second University of Naples.