Question 1

Why was albiglutide withdrawn from the market?

Accepted Answer

GlaxoSmithKline announced on July 25, 2017 that it would discontinue albiglutide for commercial reasons. The drug had launched as Tanzeum in the United States in 2014 and as Eperzan in Europe in 2014 but never captured meaningful market share against liraglutide, exenatide, dulaglutide, and the emerging semaglutide program. Reasons cited in industry coverage and analyst notes included a weaker HbA1c and weight-loss profile than competitors, higher injection-site reaction rates, and the once-weekly market increasingly being defined by Trulicity and the pipeline toward Ozempic. GSK clarified at the time that the decision was not driven by any new safety finding. Global market withdrawal was completed in July 2018, three months before HARMONY OUTCOMES read out at the European Association for the Study of Diabetes meeting.

Question 2

Does HARMONY OUTCOMES still inform GLP-1 cardiovascular class data?

Accepted Answer

Yes. Every major meta-analysis and guideline review of GLP-1 receptor agonist cardiovascular benefit published since 2018 — including the American Diabetes Association Standards of Care, the American College of Cardiology and American Heart Association cardiometabolic syndrome guidance, and pooled analyses such as the Sattar 2021 Lancet Diabetes & Endocrinology meta-analysis — includes HARMONY OUTCOMES alongside LEADER, SUSTAIN-6, REWIND, and AMPLITUDE-O as one of the trials that establishes the class effect. The reasoning is that the result was generated under a rigorous, double-blind, event-adjudicated design and that the molecular target (the GLP-1 receptor) is the same regardless of which agonist activates it. A drug being unavailable does not retroactively remove its trial data from the class-level evidence base.

Question 3

Could albiglutide ever return to the market?

Accepted Answer

It is not impossible, but as of 2026 there is no public indication that GSK or a successor company plans to relaunch albiglutide. The Biologics License Application (BLA 125431) remains on the FDA's Drugs@FDA database in a discontinued status rather than a withdrawn-for-safety status, which means the regulatory record itself does not stand in the way of a future relaunch. A relaunch would still require GSK or a licensee to restart manufacturing, address device and packaging supply, and decide that the commercial case had improved — historically a high bar for a drug that lost its niche to more potent competitors. For practical purposes prescribers should treat albiglutide as unavailable and treat HARMONY OUTCOMES as evidence about the class rather than guidance about a prescribable agent.

Question 4

How does the HARMONY OUTCOMES MACE effect size compare to LEADER and SUSTAIN-6?

Accepted Answer

HARMONY OUTCOMES reported a primary MACE hazard ratio of 0.78 (95% CI 0.68-0.90) over a median 1.6 years. LEADER (liraglutide, Marso 2016, PMID 27295427) reported 0.87 (95% CI 0.78-0.97) over a median 3.8 years. SUSTAIN-6 (semaglutide 0.5 mg and 1.0 mg, Marso 2016, PMID 27633186) reported 0.74 (95% CI 0.58-0.95) over a median 2.1 years. The point estimates land in the same range and the confidence intervals overlap; differences in follow-up duration and event rates explain most of the apparent spread. The component-level signatures differ — HARMONY OUTCOMES was MI-driven, SUSTAIN-6 was stroke-driven, LEADER was CV-death-driven — but the headline class effect is the same: roughly a 12-26% relative reduction in three-point MACE in adults with type 2 diabetes and elevated cardiovascular risk.

Question 5

Why did HARMONY OUTCOMES stop after only 1.6 years of follow-up?

Accepted Answer

The trial was event-driven, meaning it was designed to keep enrolling and following participants until a pre-specified number of primary cardiovascular endpoints had accrued. On November 8, 2017 the executive committee determined that 611 primary endpoints had occurred and that the median follow-up had reached at least 1.5 years, triggering trial close-out. Investigators called participants back for a final visit and the last patient visit was March 12, 2018. The decision to declare the threshold met arrived four months after GSK's July 2017 announcement that albiglutide would be withdrawn from the market. GSK has stated that the trial was completed under contractual obligations to enrolled participants and that the early close-out reflected pre-specified statistical criteria rather than the commercial decision. The shorter follow-up (1.6 years versus 2-5 years for LEADER, SUSTAIN-6, REWIND, and AMPLITUDE-O) is the most-cited methodological note in the published trial and one reason the cardiovascular-death component did not reach significance.

Endpoint	Treatment	Comparator	Difference
Cardiovascular death (component of MACE) Cardiovascular mortality was numerically lower but not statistically reduced. Unlike LEADER, HARMONY OUTCOMES did not show a CV-death benefit at 1.6 years — a result consistent with its shorter follow-up.	Incidence rate 1.61 events per 100 person-years on albiglutide	Incidence rate 1.72 events per 100 person-years on placebo	Hazard ratio approximately 0.93 (95% CI crossed 1.0); no significant reduction
Nonfatal myocardial infarction (component of MACE) 25% relative reduction in adjudicated myocardial infarction. MI was the single largest component contributor to the MACE win — the opposite direction-of-effect from SUSTAIN-6, where stroke dominated.	Incidence rate 2.43 events per 100 person-years on albiglutide	Incidence rate 3.26 events per 100 person-years on placebo	Hazard ratio 0.75 (95% CI 0.61–0.90); statistically significant
Nonfatal stroke (component of MACE) Directional but not statistically significant reduction in stroke. The pattern is the inverse of semaglutide's SUSTAIN-6 result and is part of the argument that individual GLP-1 receptor agonists have different cardiovascular component-level signatures.	Incidence rate 1.25 events per 100 person-years on albiglutide	Incidence rate 1.45 events per 100 person-years on placebo	Hazard ratio approximately 0.86; confidence interval crossed 1.0
MACE or urgent revascularization for unstable angina (expanded cardiovascular composite) The expanded composite tracked the primary result closely, suggesting the MI-driven benefit also affected revascularization for unstable angina.	Incidence rate 5.06 events per 100 person-years on albiglutide	Incidence rate 6.45 events per 100 person-years on placebo	Hazard ratio 0.78 (95% CI 0.69–0.89); statistically significant
Cardiovascular death or hospitalization for heart failure Directional but not statistically significant. Heart-failure hospitalization on GLP-1 receptor agonists has been a recurring null finding across the class.	Incidence rate 2.49 events per 100 person-years on albiglutide	Incidence rate 2.92 events per 100 person-years on placebo	Hazard ratio approximately 0.85; confidence interval crossed 1.0
Time to a clinically important microvascular event (composite of need for renal transplant or dialysis, new diabetes-related blindness, or photocoagulation or anti-VEGF procedures) Numerically fewer microvascular events on albiglutide; the trial was not powered to demonstrate microvascular benefit but the direction matches the renal signals seen with semaglutide and dulaglutide.	Incidence rate 0.46 events per 100 person-years on albiglutide	Incidence rate 0.69 events per 100 person-years on placebo	Hazard ratio approximately 0.66; confidence interval crossed 1.0
HbA1c change from baseline at month 16 Modest glycemic effect from a mean baseline HbA1c of 8.7%, in line with albiglutide's reputation as a less potent GLP-1 receptor agonist than liraglutide, semaglutide, or dulaglutide. The cardiovascular benefit was disproportionately large relative to the HbA1c effect, reinforcing the class argument that GLP-1 cardiovascular benefit is not driven primarily by glucose lowering.	−0.83 percentage points (least-squares mean) on albiglutide	−0.31 percentage points (least-squares mean) on placebo	Estimated treatment difference approximately −0.5 percentage points vs placebo
Body weight change from baseline at month 16 Small weight reduction, much less than the 4-15 kg seen with semaglutide and tirzepatide. Albiglutide is a long-acting GLP-1-albumin fusion that crosses the blood-brain barrier poorly, which most likely explains both the modest weight effect and the weaker satiety profile.	−1.36 kg (least-squares mean) on albiglutide	−0.53 kg (least-squares mean) on placebo	Estimated treatment difference approximately −0.8 kg vs placebo
Time to initiation of insulin of more than three months duration among participants not on insulin at baseline More than half of placebo-arm patients who would have escalated to insulin avoided it on albiglutide. A clinically meaningful glycemic-treatment-burden endpoint that did not get the spotlight at publication because the cardiovascular result dominated the headlines.	Incidence rate 3.56 events per 100 person-years on albiglutide	Incidence rate 8.58 events per 100 person-years on placebo	Hazard ratio approximately 0.42; statistically significant
Composite metabolic endpoint (HbA1c ≤7% with no severe hypoglycemia and no weight gain) at final assessment Roughly 11 percentage points more patients hit a clean composite of glycemic target without hypoglycemia or weight gain on albiglutide — the diabetes-management piece of the case for GLP-1 receptor agonists in this population, separate from the MACE story.	26.0% of participants on albiglutide	15.1% of participants on placebo	Treatment difference approximately +11 percentage points; statistically significant

Event	Treatment rate	Comparator rate
Acute pancreatitis (adjudicated) No statistically significant excess; absolute numbers low. Consistent with the class-level pancreatitis profile seen in LEADER and SUSTAIN-6.	0.2% (10/4,731)	0.1% (7/4,732)
Pancreatic cancer No imbalance between arms over the trial period.	0.1% (6/4,731)	0.1% (5/4,732)
Medullary thyroid carcinoma No cases in either arm. The black-box warning on the GLP-1 class derives from rodent C-cell tumors, not human trial signals.	0 of 4,731	0 of 4,732
Injection-site reactions Albiglutide was the GLP-1 receptor agonist most commonly associated with injection-site reactions in head-to-head comparisons, which prescribing experience cited as a reason for slow uptake.	Higher on albiglutide than on placebo (numerically the most common drug-attributable adverse event)	Lower on placebo
Treatment-related deaths (investigator-assessed, blinded) Numerically fewer on albiglutide. Investigators were masked to treatment when assigning relatedness.	2 of 4,731 (<1%)	3 of 4,732 (<1%)
Discontinuation due to adverse events Discontinuation rates in HARMONY OUTCOMES were not meaningfully elevated on albiglutide — a softer GI profile than semaglutide or liraglutide, consistent with the drug's weaker pharmacodynamic potency.	Comparable to placebo overall	Comparable to albiglutide overall

HARMONY OUTCOMES deep-dive: albiglutide MACE result for a shelved GLP-1 (Hernandez 2018)

Primary endpoint

Secondary endpoints

Adverse events

Subgroup analyses

Clinical significance

Frequently Asked Questions

References

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