Overview

Semaglutide is a glucagon-like peptide-1 (GLP-1) receptor agonist. It is currently marketed under three different brand names: Ozempic®, Wegovy®, and Rybelsus®. With actions of lowering blood sugar, reducing the risk of cardiovascular disease, and suppressing appetite to facilitate weight loss, some may wonder, is this medication a solve all? Not all brand names of semaglutide have the same indications with the FDA nor the same formulations, and access due to cost differs between them. The right semaglutide formulation needs to be chosen with a full understanding of these differences to ensure the therapy selected will match the specific clinical needs of the patient and also align with the capabilities of the patient for ease of adherence to dosing instructions. With the growing patient and physician preference for GLP-1s, it is worth asking, when should it be used?

How Do Semaglutide Medications Differ?

While Ozempic, Wegovy, and Rybelsus contain the same active ingredient, their clinical characteristics differ. To better understand these differences, below are some informational tables that point out their differences with regards to their storage, dosage, FDA-approved Indications, and dosing schedules.

Choosing the Right Semaglutide for a Patient

Selecting the appropriate semaglutide product depends on the patient’s indication, preferred route of administration, comorbidities, and ability to adhere to required dosing instructions. For example, Rybelsus® is appropriate for patients who prefer an oral option and are willing to follow strict administration requirements (e.g. empty stomach).

Adverse Effects & Safety

Adverse Effects

• Gastrointestinal: The most common adverse effects of GLP-1RA therapies are gastrointestinal which include nausea, vomiting, constipation, diarrhea, and abdominal pain. In addition, decreased appetite, dysgeusia, and dyspepsia have also been reported. The majority of GLP-1RA treatment regimens reported nausea as the most frequent gastrointestinal side effect, particularly when beginning a GLP-1 or shortly following dose. To mitigate this, meal portioning can help lower the chance of this adverse effect. 

• Hypoglycemia: GLP-1 agonists can result in hypoglycemia by lowering blood glucose. When semaglutide is taken with other anti-hyperglycemic drugs such insulin, metformin, or sulfonylureas, the risk of hypoglycemia increases considerably. 

• Renal: Incidences of acute kidney injury more likely to occur in patients who had nausea, vomiting, diarrhea, or dehydration during therapy. It has been suspected to be linked with volume depletion or insufficient hydration.

• Gallbladder disorders: Semaglutide has been linked to biliary tract and gallbladder problems, such as cholecystitis and cholelithiasis. The mechanism is unclear exactly how this adverse effect occurs. 

• Risk of thyroid C-cell tumors: Animal trials using semaglutide during the early stages of drug development showed a risk of thyroid C-cell tumors. However, it is currently unknown whether semaglutide and thyroid malignancies in humans are related. People who have been diagnosed with multiple endocrine neoplasia type 2 (MEN2) syndrome or who have a personal or family history of medullary thyroid carcinoma (MTC) may be at higher risk.Other adverse reactions: Fatigue, headache, soreness at the injection site, and erythema at the injection site.

• Other adverse reactions: Fatigue, headache, soreness at the injection site, and erythema at the injection site.

Precautions/Warnings/Contraindications

• Semaglutide may affect the absorption of concurrently given oral drugs since it delays the emptying of the stomach. In research, semaglutide had no clinically significant impact on the absorption of drugs taken orally. However, when taking oral drugs along with semaglutide, caution should be used.

• To minimize the risk of transmitting infectious diseases, individuals shouldn’t share the multiple-dose injectable pen (Ozempic®).

• When using semaglutide, patients with a history of bariatric surgery are more likely to experience gastrointestinal issues. Regular monitoring in these individuals is recommended.

• Rebound weight gain has been seen with the discontinuation of GLP-1 RAs. Participants in the STEP 1 trial regained almost two-thirds of their original weight loss after stopping weekly subcutaneous semaglutide (Wegovy®) 2.4 mg and lifestyle modifications for a year.

• GLP-1 RAs are contraindicated with personal or family history of MTC or in patients with MEN2. Semaglutide is also contraindicated in patients with type 1 diabetes.

Cost Barriers

Insurance plans differ in their coverage of weight-loss drugs. Wegovy® and other prescription drugs used just for weight loss may not be covered by many insurance companies, or they may need prior authorization. Many individuals pay out of pocket monthly using manufacturer coupons, but paying high costs long-term may not be attainable. FDA-approved GLP-1 RAs such as Ozempic® and Rybelsus® may be covered by your insurance if you have T2DM.

Overall, semaglutide is available as Ozempic®, Wegovy®, and Rybelsus®, each designed for different therapeutic goals and delivered through distinct dosage forms and dosing schedules. Selecting the right formulation requires aligning the product with a patient’s clinical needs, preferred route of administration, and ability to adhere to specific instructions. While semaglutide offers significant benefits for diabetes, weight management, and cardiovascular health, it also carries important safety considerations and potential side effects that must be addressed prior to initiation. In addition, access and coverage can vary significantly, making these important factors in choosing the most appropriate therapy.

Lauren T., APPE Student

References

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