TAMARIN trial

Chief investigator - Professor Claire Harrison, Guys and St Thomas’ NHS Foundation Trust
A phase II trial to assess the effects of tamoxifen on the mutant allele burden and disease course in patients with myeloproliferative neoplasms
Award start date: 01 Dec 2015
Recruitment start date: 26 Aug 2016
Award duration: 3 years (36 months)

This study is for people with a type of blood disorder called myeloproliferative neoplasms (MPN) that causes the bone marrow to produce too many blood cells. This includes: polycythaemia vera (PV), essential thrombocythaemia (ET) and myelofibrosis (MF).

People with PV produce too many red blood cells, causing the blood to become thicker than normal. ET occurs when there are too many platelets in the blood, which can cause the blood to clot. People with MF have an overactive bone marrow, which develops scar tissue (known as fibrosis). The scar tissue builds up inside the bone marrow preventing the normal development of blood cells and can cause complications including anaemia.

Many people with MPN have changes to the JAK2 and CALR genes found in blood cells. There are already some treatments that target cells that have these gene changes, including ruxolitinib. Ruxolitinib inhibits the abnormal JAK signalling associated with changes to the JAK2 gene, and stops cancer cells from growing and dividing. Ruxolitinib and other treatments, such as interferon and hydroxycarbamide, have helped people with MPN. But some are unable to tolerate the side effects of these treatments, so researchers are looking for new ways to treat MPN.

Tamoxifen is a drug currently used to treat breast cancer and laboratory research indicates it could be beneficial for people with MPN who have the JAK2 and the CALR gene changes. 

In this study, people will have tamoxifen alongside the usual treatment for their MPN.

The aim of this trial is to:

  • See if adding tamoxifen helps to reduce the number of cells carrying the JAK2 and CALR genetic changes

You may be eligible to join this trial if:

  • You have had PV, ET, or MF for six months or longer
  • You have the JAK2 or CALR gene change
  • You are aged 60 or older
    • Men with an MPN aged between 50 to 59 may be able to take part - the study team would confirm this