Two cases of pancreatic carcinoma were reported in patients receiving dulaglutide in the completed phase 2 and phase 3 studies. These 2 patients both

• had a shorter duration of diabetes that was ≤3 years, and
• a baseline body mass index (BMI) less than 25 kg/m².1

The first patient was diagnosed with a large, nonresectable tumor 1 week after their first and only dose of dulaglutide 0.75 mg.1

The second patient, after approximately 5 months of exposure to dulaglutide, was found to have a large tumor that consumed most of the body and tail of his/her pancreas.1

No patients who received placebo or any active comparator reported pancreatic cancers.1

Results from phase 2 and phase 3 clinical studies do not suggest an increased incidence of malignancy in general or any specific malignancy type with dulaglutide treatment. However, for a rare disease with a long latency period like pancreatic cancer, malignancies in ongoing studies will continue to be carefully assessed in addition to risk assessment through postmarketing cases and exposure.1

REWIND was an event-driven, randomized, double-blind, placebo-controlled study of dulaglutide with a median follow-up duration of 5.4 years.2

The study evaluated the effect on major adverse cardiovascular events (death due to cardiovascular causes or unknown causes, nonfatal myocardial infarction, or nonfatal stroke) (MACE-3) and other serious outcomes with once-weekly dulaglutide 1.5 mg treatment compared with placebo when added to standard of care in participants 50 years of age and older with type 2 diabetes and established cardiovascular disease and/or risk factors.2

During REWIND, pancreatic cancer was a prespecified adverse event of special interest.2

• Of the 4949 patients receiving dulaglutide, 19 patients experienced pancreatic cancer.
• A total of 4952 patients received placebo, 12 of which reported having pancreatic cancer.
• The frequency of a prespecified adverse events, such as pancreatic cancer, did not differ significantly between the dulaglutide and placebo treated groups.2

In the phase 3 clinical development program for dulaglutide 3.0 mg and 4.5 mg, 1 case of pancreatic adenocarcinoma was reported in a patient assigned to the dulaglutide 1.5 mg treatment group.1

The patient was diagnosed 39 days after completing the safety follow-up period and 74 days after his/her last dose of dulaglutide.1

Postmarketing data do not necessarily represent the rate of occurrence of an adverse event in a treated population, but they represent a reporting rate of a particular adverse event to the company. Spontaneous reporting of adverse events can be highly variable and is not appropriately controlled clinical information on which to base an assessment of whether a particular drug product is the causal agent of an adverse event.1

Spontaneous reporting has limited use due to

• lack of control population
• under-reporting or reporting bias, and
• missing or incomplete information regarding patient's medical history or concomitant medications.1

The Eli Lilly and Company (Lilly) spontaneous adverse event database may also include reports of adverse events for products that may be available from Lilly and from other manufacturers. Although verification of product manufacturer is sought, this verification is not always obtainable. The default for these cases is to include them in the database.1

Lilly is currently sponsoring an observational study on dulaglutide and the potential risk of pancreatic and thyroid cancer. More information about the study can be found here.1

In a 6 month carcinogenicity study in transgenic mice, there was no tumorigenic response.3 

In a 2 year carcinogenicity study in rats, at ≥ 3 times the human clinical exposure following 4.5 mg dulaglutide per week, dulaglutide caused statistically significant, dose-related increases in the incidence of thyroid C-cell tumours (adenomas and carcinomas combined). The clinical relevance of these findings is currently unknown.3