Drug Name
Mounjaro™ (tirzepatide)
Developer
Eli Lilly and Company
Therapy Class
Glucose-dependent insulinotropic polypeptide (GIP) receptor and glucagon-like peptide-1 (GLP-1) receptor agonist
Current Indication
Type 2 diabetes
Market Sector
Diabetes
Development Status
Approved in the US
Mounjaro™ (tirzepatide) is a dual-targeted, injectable therapy indicated for the management of type 2 diabetes (T2D) in adults as an adjunct to diet and exercise.
Developed by US-based pharmaceutical company Eli Lilly, Mounjaro is the first and only once-weekly glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonist to improve blood glucose levels in adult type 2 diabetics.
Mounjaro was approved by the US Food and Drug Administration (FDA) for its indication in May 2022 after receiving priority review designation. The drug is also being reviewed by the regulatory authorities in Europe, Japan and several other countries for T2D treatment.
Mounjaro is available as a clear, colourless to slightly yellow solution in six doses. It comes in pre-filled single-dose auto-injector pens for subcutaneous administration.
Type 2 diabetes signs and symptoms
T2D is a chronic and progressive condition in which blood sugar regulation in the body is impaired, causing excessive sugar circulation in the bloodstream. High blood sugar levels can lead to circulatory, nervous, and immune system disorders.
T2D is the most common form of diabetes. It develops slowly and individuals with the condition can remain asymptomatic for years. Signs and symptoms of the disease can include increased thirst and hunger, frequent infection and urination, unintended weight loss, blurred vision, fatigue, slow-healing sores, and numbness or tingling sensations in the hands and feet.
Mounjaro’s mechanism of action
Mounjaro (tirzepatide) is a single molecule that selectively binds to and activates both the GIP and GLP-1 receptors to target GIP and GLP-1, the native incretin hormones.
The activation improves the secretion of both first and second-phase insulin and reduces glucagon levels, both in a glucose-dependent manner.
Clinical trials on Mounjaro
The FDA’s approval of Mounjaro was based on positive outcomes from a Phase III SURPASS programme that included five clinical trials, namely SURPASS-1, SURPASS-2, SURPASS-3, SURPASS-4 and SURPASS-5.
In SURPASS-1, Mounjaro was studied as a monotherapy. In SURPASS-2, SURPASS-3 and SURPASS-4, the drug was studied as an add-on to the common diabetes medications metformin, sulfonylureas, and/or sodium-glucose co-transporter 2 inhibitors (SGLT2 inhibitors). For SURPASS-5, Mounjaro was evaluated in combination with basal insulin with or without metformin.
Three doses of Mounjaro 5mg, 10mg and 15mg were used for evaluating the efficacy of the drug in the SURPASS programme. The doses were administered subcutaneously once weekly for comparison with placebo (SURPASS-1), semaglutide 1mg (SURPASS-2), insulin degludec (SURPASS-3), and/or insulin glargine (SURPASS-4).
The doses, in combination with basal insulin with or without metformin, were compared with placebo in T2D patients during the SURPASS-5 clinical study.
Patients with T2D who participated in the SURPASS programme achieved reductions of between 1.8% and 2.1% in their blood glucose levels on an average for Mounjaro 5mg dose, and between 1.7% and 2.4% for both 10mg and 15mg doses of Mounjaro.
Mounjaro delivered superior blood glucose level reductions against all comparators in the SURPASS programme. Use of the drug also led to significantly greater weight loss in patients than other comparators. The patients treated with 5mg dose lost 12lb of weight, while those treated with 15mg dose saw their weight reduce by 25lb.
The most common side effects reported in patients during the clinical trials were nausea, diarrhoea, decreased appetite, vomiting, constipation, indigestion, and abdominal pain.