Lanreotide Cut Neuroendocrine Tumor Progression Risk by 53% in Landmark CLARINET Trial | Research

The takeaway

The CLARINET trial showed that monthly lanreotide injections cut disease progression risk by 53% in patients with metastatic neuroendocrine tumors, leading to FDA approval.

53% risk reduction (HR 0.47)
Lanreotide cut the risk of disease progression or death nearly in half compared to placebo in metastatic neuroendocrine tumor patients over 96 weeks

What the researchers found

In the landmark CLARINET trial, lanreotide (a long-acting somatostatin analog) cut the risk of tumor progression or death by 53% compared to placebo in patients with metastatic neuroendocrine tumors of the gut and pancreas (hazard ratio 0.47, p<0.001). After 96 weeks, 65.1% of lanreotide patients had no disease progression compared to just 33.0% on placebo.

The median progression-free survival wasn't even reached in the lanreotide group (vs. 18 months for placebo), meaning more than half the patients were still progression-free at study end. The treatment effect was consistent across subgroups, and quality of life was similar between groups.

Why it matters

CLARINET was the definitive trial that established lanreotide as a first-line antiproliferative treatment for well-differentiated neuroendocrine tumors, directly leading to FDA approval. Before this study, somatostatin analogs were primarily used for symptom control; CLARINET proved they actually slow tumor growth. Published in the New England Journal of Medicine, this is one of the most important studies in neuroendocrine tumor treatment.

The numbers in context

n=204 · 96 weeks · HR 0.47 (95% CI 0.30–0.73) · p<0.001 · PFS at 24 months: 65.1% vs 33.0% · Median PFS: not reached vs 18.0 months · Diarrhea: 26% · Abdominal pain: 14%

How the study worked

Phase 3, double-blind, placebo-controlled, multinational trial (CLARINET). 204 patients with well-differentiated or moderately differentiated, nonfunctioning, somatostatin receptor-positive, grade 1 or 2 (Ki-67 <10%) metastatic enteropancreatic neuroendocrine tumors were randomized to lanreotide 120 mg or placebo injected every 28 days for 96 weeks. Primary endpoint was progression-free survival.

Who was studied

204 patients with metastatic grade 1/2 enteropancreatic neuroendocrine tumors, somatostatin receptor-positive, nonfunctioning

What this study cannot tell us

Only included grade 1/2 tumors (Ki-67 <10%) — results may not apply to more aggressive grade 3 neuroendocrine tumors. Only nonfunctioning tumors were included (those not producing excess hormones). Many patients had stable disease at entry, which could bias toward favorable outcomes. The study did not demonstrate an overall survival benefit.

How to read the evidence

This is strong-grade evidence from a phase 3, double-blind, placebo-controlled RCT published in the New England Journal of Medicine. The trial was well-designed with a meaningful clinical endpoint and led directly to regulatory approval.

When this study was published

Published in 2014, CLARINET remains the definitive trial for lanreotide in neuroendocrine tumors and continues to guide clinical practice worldwide. Its findings have been reinforced by subsequent long-term follow-up data.

The bigger picture

CLARINET transformed the treatment of neuroendocrine tumors by proving that somatostatin analogs aren't just symptom management — they're actual anticancer therapy. Together with the earlier PROMID trial (which tested octreotide), it established somatostatin analogs as the foundation of neuroendocrine tumor treatment worldwide. This trial remains a cornerstone reference in oncology guidelines.

Questions still open

Does lanreotide provide an overall survival benefit in addition to delaying progression?
Would lanreotide be effective in higher-grade (grade 3) neuroendocrine tumors or functioning tumors?
How does lanreotide compare to newer peptide receptor radionuclide therapy (PRRT) as first-line treatment?

Common questions

What is lanreotide and how does it treat cancer?

Lanreotide is a synthetic version of somatostatin, a natural hormone that tells cells to stop growing and dividing. Neuroendocrine tumor cells have receptors for somatostatin, so lanreotide binds to these receptors and slows tumor growth. It's given as a monthly injection and is one of the first-line treatments for slow-growing neuroendocrine tumors.

Is lanreotide a cure for neuroendocrine tumors?

No — lanreotide slows tumor growth but doesn't cure the cancer. In this trial, it kept tumors stable significantly longer than placebo (most patients still hadn't progressed after 2 years). It's typically used as long-term treatment to control disease progression, often in combination with other approaches for more advanced cases.

Read the original research

Lanreotide in metastatic enteropancreatic neuroendocrine tumors.

The New England journal of medicine, 371(3), 224-33

View on PubMed ↗Publisher’s paper ↗

Citation

Caplin, Martyn E; Pavel, Marianne; Cwikla, Jaroslaw B; Phan, Alexandria T; Raderer, Markus; Sedlackova, Eva; Cadiot, Guillaume; Wolin, Edward M; Capdevila, Jaume; Wall, Lucy; Rindi, Guido; Langley, Alison; Martinez, Santiago; Blumberg, Jochen; Ruszniewski, Philippe; CLARINET Investigators. (2014). Lanreotide in metastatic enteropancreatic neuroendocrine tumors.. The New England journal of medicine, 371(3), 224-33. https://doi.org/10.1056/NEJMoa1316158