New Medicines

Inrebic · Myelofibrosis


New molecular entity

Development and Regulatory status

Phase III Clinical Trials
Phase III Clinical Trials
Approved (Licensed)

Aug 19: FDA approved Inrebic for treatment of adult patients with intermediate-2 or high-risk primary or secondary (post-polycythemia vera or post-essential thrombocythemia) myelofibrosis [16].

Mar 19: Accepted for priority review in US, with a target action date of 3/9/19 [13].

Jul 18: Celgene plans to file fedratinib before the end of 2018 [12].

Mar 18: Celgene is now developing fedratinib. PIII development has resumed in EU & US [10].

Oct 17: FDA lifts hold on clinical trials of fedratinib after reviewing additional data provided by Sanofi. One of the factors taken into consideration are they very limited therapeutic options available for these patients so benefit may outweigh risk in some. Re-investment into the product may lead to further development by Impact Biosciences. [9]

Nov 13: Sanofi discontinues development of fedratinib, following reports of cases consistent with Wernicke’s encephalopathy in patients participating in studies. The US FDA had told Sanofi to put all fedratinib trials on clinical hold while the company thoroughly investigated the cases [8].

May 13: Filings are being planned [7].

Orphan drug status in the EU [2] and the US [3].

PIII study to start Oct 11 [1].


Selective inhibitor of Janus kinase 2 (JAK2) and FLT-3 tyrosine kinase
In the EU, primary myelofibrosis affects ~0.3 in 10,000 people (15,000 people), post-essential thrombocythaemia myelofibrosis affects < 0.01 in 10,000 people (<500 people) and post-polycythaemia vera myelofibrosis affects < 0.15 in 10,000 people (<8,000 people).

Further information

To be confirmed

Trial or other data

Oct 17: JAKARTA-2 trial meets its primary endpoint [11].

Apr 14: PII JAKARTA-2 trial investigating efficacy and tolerability of fedratinib in patients with intermediate-2 or high-risk myelofibrosis, following polycythaemia vera or essential thrombocythaemia, who had previously been treated with another JAK2 inhibitor, ruxolitinib completes (NCT01523171). The follow-on study enrolled 97 patients in Austria, Belgium, Canada, France, Germany, Italy, Netherlands, Spain, United Kingdom, and the US [11].

May 13: The pivotal study, JAKARTA, examining the selective JAK2 inhibitor SAR302503 for myelofibrosis (MF), met its primary endpoint in both dose groups. Results will be published at a forthcoming conference. [6]

Jan 13: Recruitment to the PIII JAKARTA study is complete and headline results are expected Q2 2013 [5].

Dec 12: New data from A PII study reported. The open label, randomized dose-ranging study evaluated the once-daily oral doses of 300mg, 400mg and 500mg of SAR302503. Spleen volume at the end of cycle three assessed by MRI with independent central review (primary endpoint) was reduced vs baseline by a mean of 30% (n=10), 33% (n=10) and 42% (n=11), in each group, respectively. The proportion of patients who achieved a ≥35% reduction in spleen volume by MRI was 30%, 50% and 63.6% in each group, respectively. The proportion of patients who achieved ≥50% reduction in the Myeloproliferative Neoplasm Symptom Assessment Form (MPN-SAF) score, a sum of six key constitutional symptoms (night sweats, itching, abdominal discomfort, abdominal pain, bone pain, early satiety), was similar in all groups (44-50%). The most common serious (grade 3-4) haematologic adverse event was anaemia ( 33%, 30% and 55%, respectively). Rates of grade 3-4 thrombocytopenia were 20%, 0% and 9%, respectively. The most common grade 3-4 non-haematological events were diarrhoea (10%, 20%, 0%), nausea (10%, 10%, 0%) and vomiting (10%, 10%, 0%). Two patients in the 300mg group discontinued treatment due to an adverse event (grade 3 anaemia, grade 4 transaminase elevation) [4].

Sep 11: NCT01437787 (JAKARTA) - A PIII, multicenter, randomized, double-blind study of SAR302503 in 225 patients with intermediate-2 or high-risk primary myelofibrosis, post-polycythemia vera myelofibrosis, or post-essential thrombocythemia myelofibrosis with splenomegaly. The primary objective is to evaluate the efficacy of daily oral doses of 400 or 500mg of SAR302503 vs placebo in the reduction of spleen volume as determined by MRI (or CT scan in patients with contraindications for MRI). The primary outcome is response rate, defined as the proportion of patients who have a ≥35% reduction in volume of spleen size at the end of cycle 6, and confirmed 4 weeks thereafter (time frame: 6 months). Patients who continue to benefit clinically will be allowed to remain on SAR302503 or placebo beyond the 6-month treatment period until the occurrence of disease progression or unacceptable toxicity. The study will start Oct 11 and is due to complete Jan 16 (date for primary outcome data collection Feb 13) [1].

Evidence based evaluations