Netter-1 study


Lutetium Lu 177 dotatate is under investigation, and the safety and effectiveness have not been fully evaluated by a regulatory authority.

Results now available

The investigational NETTER-1 Study results are now available. The pivotal Phase III NETTER-1 study for Lutetium Lu 177 dotatate met its primary endpoint of assessing progression-free survival (PFS), demonstrating that Lutetium Lu 177 dotatate significantly improved PFS when compared with Sandostatin LAR 60mg (Octreotide LAR) in patients with advanced midgut neuroendocrine tumors (NETs).

Lutetium Lu 177 dotatate

Lutetium Lu 177 dotatate is a novel investigational drug currently under development for the treatment of midgut neuroendocrine tumours. Lutetium Lu 177 dotatate belongs to an emerging form of treatments called peptide receptor radionuclide therapy (PRRT) which involves targeting carcinoid tumors with radiolabeled somatostatin analogue peptides.


zèbre-BThe unmet medical need for an effective treatment of inoperable, advanced neuroendocrine tumors (NETs) is well known. There are no therapeutic options for patients with NETs other than pancreatic (about 90% of NETs) who are progressive under somatostatin analogues.

PRRT meets this specific medical need and leading key scientific societies such as NANETS1, ESMO2 and ENETS3 have included this therapy in their treatment guidelines for non-resectable midgut or gastro-entero-pancreatic NETs.

Furthermore, preliminary scientific evidence of tumor-targeted PRRT has urged several European countries (currently Austria, Denmark, Estonia, Finland, France, Greece, Portugal, Spain, Switzerland, UK) to implement compassionate use/named patient basis programs. Hence, since 2000, thousands of patients have been treated with 177Lu-DOTA0-Tyr3-Octreotate (177Lu Dotatate) showing promising results.

Currently at the end of phase III development with the Netter-1 pivotal study, Lutetium Lu 177 dotatate is the most advanced candidate in development for PRRT.

Trial Overview

Design: Netter-1 is the first Phase III multi-center, stratified, open, randomized, controlled, parallel-group study, comparing 177Lu Dotatate with Octreotide LAR (Sandostatin® LAR Depot) in patients with inoperable, progressive, somatostatin receptor positive midgut carcinoid tumours.

Primary endpoint: Progression Free Survival (PFS) as per RECIST 1.1 criteria. Objective tumor assessment is performed every 12 weeks until progression is documented using an independent image reading center.

Main secondary endpoints: Objective Response Rate (ORR), Overall Survival (OS), Time To Progression (TTP), safety, tolerability and health-related quality of life. Dosimetry, pharmacokinetics and ECG evaluations are also performed in a subset of patients.

Protocol Summary

Protocol: Treatment with a cumulative dose of 29.6 GBq of 177Lu Dotatate (4 administrations of 7.4 GBq every 8 weeks) plus supportive care with 30 mg Sandostatin® LAR on one arm. Compared to 60 mg Sandostatin® LAR alone every 4-weeks on the other arm. Patients must have progressive disease while on a fixed dose of Sandostatin® LAR at baseline. Presence of somastotatin receptors on all target lesions shall be confirmed by OctreoScan® imaging.

The OS period includes 18-month accrual plus a 5-year follow-up starting from the last patient’s randomization date. Tumor response is centrally assessed in both arms, every 12 +/-1 week(s) from the randomization date, according to the RECIST criteria. Efficacy is blindly and independently assessed through image review by qualified readers.

Patients shall remain under treatment until disease progression or unacceptable toxicity or inability/unwillingness to comply with study requirements or consent withdrawal.

Participating sites: 36 in Europe and 15 in the USA.


The first patient was enrolled in July 2012. The study is designed to randomize 230 patients, 1:1 to each arm.

The Analysis of primary endpoint (PFS) started after 74 evaluable and centrally confirmed events.

An independent Data Safety Monitoring Board (DSMB) is supervising the conduct of the study and regularly assesses the study safety outcome.

More information on the Netter-1 trial can be found at:

177Lu-DOTATATE Mode of Action video  


  1. Boudreaux et al. 2010, The NANETS Consensus Guidelines for the Diagnosis and Management of Neuroendocrine Tumors.
  2. Eriksson et al. 2008, Consensus Guidelines for the Management of Patients with Digestive Neuroendocrine Tumors – Well-differentiated Jujenal-Ileal Tumor/Carcinoma (ENETS Guidelines)
  3. Oberg et al. 2012, Neuroendocrine Gastro-entero-pancreatic tumors : ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up.