Saxenda After Bariatric Surgery: What Clinicians and Patients Need to Know

Does the Saxenda label cover use after bariatric surgery?

The Saxenda label's indication is based on body size and weight-related conditions: adults with overweight and at least one weight-related comorbid condition, and adults and pediatric patients aged 12 years and older with body weight above 60 kg and obesity [3]. Bariatric surgery is not specifically addressed in the indication [3]. The labeled adult dose is 3 mg once daily, reached by weekly steps, and the label says coadministration with other liraglutide-containing products or any other GLP-1 receptor agonist is not recommended [3].

Saxenda is given by subcutaneous injection in the abdomen, thigh or upper arm [3]. The label reports absolute bioavailability of about 55%, peak levels at about 11 hours and a half-life of about 13 hours, with once-daily dosing [3].

What the post-bariatric evidence shows

A 2013 retrospective series treated 15 patients after bariatric surgery [1]. All 15 had either lost less than 50% of their excess weight two years after the operation or regained more than 15% of their lowest weight, and all had anatomy that looked as expected on contrast radiography and endoscopy. They received liraglutide at 1.2 to 3.0 mg a day for 8 to 28 weeks. Mean weight fell from 100.9 kg to 93.5 kg (P<0.0001). Six patients had nausea, and two stopped treatment because of the cost of the medication [1].

Surgery had produced a mean loss of 34.1 kg in these patients, followed by a mean regain of 14.2 kg over 5.3 years before liraglutide was started [1]. The series has no placebo group, used a range of doses and followed patients for a few months, so it shows that weight fell in these 15 people without showing how much of the fall came from the drug [1].

What the larger weight-loss trials found

The largest trial, SCALE Obesity and Prediabetes, randomized 3,731 adults with a BMI of at least 30, or at least 27 with treated or untreated dyslipidemia or hypertension, to liraglutide 3.0 mg (2,487 people) or placebo (1,244) for 56 weeks, with lifestyle counseling in both groups [4]. Mean weight fell by 8.4 kg on liraglutide and 2.8 kg on placebo, a difference of 5.6 kg (95% CI -6.0 to -5.1) [4]. At least 5% of body weight was lost by 63.2% versus 27.1%, and more than 10% by 33.1% versus 10.6% [4]. The label's analysis of the same trial, using a different method for missing weights, reports -7.4% versus -3.0% of body weight [3].

SCALE Maintenance enrolled 422 adults who had already lost at least 5% of their body weight during a low-calorie diet run-in, then randomized them to liraglutide 3 mg or placebo for 56 weeks [5]. Weight fell a further 6.2% on liraglutide and 0.2% on placebo, and 81.4% versus 48.9% kept at least 5% of the run-in loss [5]. In this trial a drug was added to hold or extend weight already lost, though the earlier loss came from a diet rather than an operation [5].

Dosing and titration

The labeled adult schedule starts at 0.6 mg once daily and increases weekly to 3 mg from week 5 onward [3]. The recommended adult dose is 3 mg daily; lower doses are for titration only, and the label says to discontinue Saxenda if the 3 mg dose cannot be tolerated [3]. If an increase is not tolerated, the label says to consider delaying it by approximately one additional week [3].

The label directs an assessment of body weight 16 weeks after starting and discontinuation if less than 4% of baseline body weight has been lost [3]. The label says that if a dose is missed, the next scheduled dose is taken as usual with no extra dose, and that if more than 3 days have passed since the last dose, treatment restarts at 0.6 mg and follows the escalation schedule again [3]. The label lists the abdomen, thigh or upper arm as injection sites and advises rotating sites within the same region to reduce the risk of cutaneous amyloidosis; no dose adjustment is needed when the site or timing changes [3].

Safety points from the label

Hypoglycemia

The label warns that hypoglycemia can occur in adults when Saxenda is used with an insulin secretagogue such as a sulfonylurea, or with insulin, and that the risk may be lowered by reducing the dose of those drugs [3]. Among adults with type 2 diabetes taking a sulfonylurea in the Saxenda trials, glucose below 54 mg/dL occurred in 28.2% on Saxenda versus 12.7% on placebo, with sulfonylurea doses cut by 50% at the start of the trial [3]. In the adolescent trial, where participants did not have diabetes, hypoglycemia (below 70 mg/dL with symptoms) was reported in 15.2% on Saxenda versus 4% on placebo [3].

Gastric bypass has its own hypoglycemia association: in a nationwide Swedish cohort of 5,040 people who had obesity surgery, hospitalization-related hypoglycemia affected 0.2% of gastric bypass patients versus 0.04% of matched general-population participants, an adjusted hazard ratio of 2.7 (95% CI 1.2 to 6.3) [2]. The study found no increased risk after vertical banded gastroplasty or gastric banding [2].

Nausea, vomiting and the gastrointestinal tract

In the adult trials (3,384 on Saxenda versus 1,941 on placebo), nausea occurred in 39.3% versus 13.8%, diarrhea in 20.9% versus 9.9%, constipation in 19.4% versus 8.5% and vomiting in 15.7% versus 3.9%; nausea became less frequent as treatment continued [3]. Adverse reactions led 9.8% of Saxenda-treated patients and 4.3% of placebo-treated patients to stop treatment [3]. The label states that Saxenda is not recommended in patients with severe gastroparesis [3].

Gallbladder disease

Cholelithiasis was reported in 2.2% of Saxenda-treated adults versus 0.8% on placebo, and cholecystitis in 0.8% versus 0.4%; most Saxenda-treated patients with these events required cholecystectomy [3]. The label notes that the incidence was higher on Saxenda even after accounting for the degree of weight loss, and that suspected gallstones call for gallbladder studies and clinical follow-up [3].

Pancreatitis

The label warns that acute pancreatitis has been observed with GLP-1 receptor agonists including Saxenda, with instructions to discontinue if pancreatitis is suspected [3]. The January 2024 label version reported adjudicated acute pancreatitis in 0.3% of liraglutide-treated adults versus 0.1% of placebo-treated adults in the Saxenda trials [6].

Thyroid tumors

Liraglutide caused dose- and duration-dependent thyroid C-cell tumors in rats and mice at clinically relevant exposures; whether it does so in humans is unknown [3]. Saxenda is contraindicated in people with a personal or family history of medullary thyroid carcinoma or MEN 2, and routine calcitonin measurement or thyroid ultrasound is of uncertain value for early detection [3].

Heart rate, kidneys, anesthesia and pregnancy

Resting heart rate rose by a mean of 2 to 3 beats per minute, and 34% of Saxenda-treated patients versus 19% on placebo had rises above 10 beats per minute at two consecutive visits; the label says to monitor heart rate at regular intervals [3]. Acute kidney injury from volume depletion is listed as a warning, with renal function monitoring in patients reporting reactions that could lead to volume depletion [3]. Pulmonary aspiration during general anesthesia or deep sedation has been reported in patients receiving GLP-1 receptor agonists who underwent elective surgeries or procedures [3]. The label says Saxenda should be discontinued when pregnancy is recognized [3].

Oral medicines

Saxenda delays gastric emptying and may affect absorption of oral medicines; in clinical pharmacology trials liraglutide did not affect the absorption of the tested oral drugs to a clinically relevant degree, and the label's instruction is to monitor for potential consequences of delayed absorption [3]. In a study with an oral contraceptive containing 0.03 mg ethinylestradiol and 0.15 mg levonorgestrel, liraglutide lowered peak ethinylestradiol levels by 12% and levonorgestrel by 13%, did not change ethinylestradiol exposure overall, raised levonorgestrel exposure by 18% and delayed time to peak by 1.5 hours; the label gives no instruction to switch or add contraception [3].