Clinical efficacy

In patients diagnosed with ITP, Tavlesse delivered robust improvements in platelet counts^1-3

Stable response rates achieved in the 24-week evaluation period (double-blind, placebo-controlled trials)^{2, 3}

Graph showing Tavlesse response rate in 24 weeks compared to placebo.

Stable response (Primary endpoint)^{1, 6,} *

Platelet counts ≥ 50,000 /μL during weeks 14-24 (at least 4 of 6 consecutive visits)
Median post-baseline platelet count: 95,000 /μL

*Stable response was defined as platelet counts ≥50,000/μL on at least 4 of the 6 clinic visits occurring every 2 weeks during weeks 14-24 inclusive.
†Pooled analysis (FIT-1 + FIT-2) 17% of patients treated with Tavlesse achieved a stable response vs 2% of placebo treated patients (p=0.0071)

Overall response rates achieved in the 24-week evaluation period (double-blind, placebo-controlled trial)¹

Graph showing the overall response rates in the 24-week evaluation period of the treatment for chronic ITP patients.

Overall response (post hoc endpoint)^{1, 6, ✝}

At least one platelet count ≥ 50,000 /μL during weeks 0-12
Median post-baseline platelet count: 49,000 /μL
Median time to first response: 15 days in overall responders

*Overall response was defined as platelet count ≥50,000/μL within the first 12 weeks without rescue medication in the preceding 4 weeks
†Pooled analysis (FIT-1 + FIT-2) 43% of patients treated with TAVLESSE achieved an overall response vs 14% of placebo treated patients (p=0.0006)

Tavlesse overall response summary – day 1 to 24 weeks¹

Median platelet counts by study visit - overall responders (pooled FIT + FIT2)

Graph and table showing the overall response summary from day 1 to week 24.

Study visits (weeks)	0	2	4	6	8	10	12	14	16	18	20	22	24
Overall responders (n=43)	43	38	41	40	40	38	37	31	27	26	23	21	20
Non-responders (n=58)	58	48	45	41	40	39	42	7	7	5	4	3	4
Placebo (n=49)	49	43	41	35	31	33	32	11	6	3	4	2	3

First platelet count measurement at week 2 and every 2 weeks thereafter¹

A total of 102 patients exited the placebo-controlled trials early (at or after week 12) and entered the open-label extension study^2,3

Durable benefit

Tavlesse demonstrated durable increase in platelet levels for up to 3 years

Overall response observations from a 3-year post hoc interim analysis.^{4, *, †}

Median platelet counts over time (Overall responders in the phase 3 clinical studies–FIT-1 + FIT-2 + FIT-3)

Graph showing the increase in platelet levels in patients with chronic ITP that received Tavlesse during 3 years.

Patients were evaluated every 2 weeks in the placebo-controlled trials (FIT-1 + FIT-2) and no less often than monthly for 18 months, and then bimonthly for up to 5 years in the open-label extension study (FIT-3)^{1, 5}
A total of 102 patients exited the placebo-controlled trials early (at or after week 12) and entered the open-label extension study (FIT-3)^2,3

*1 month = 4 weeks. Data cut off date: 8 March 2018.
†Overall response: achievement of a platelet count ≥50,000 /μL at least once during the first 3 months/12 weeks without need for rescue treatment.

Patient subgroups

Tavlesse demonstrated efficacy across patient subgroups (overall responder population) compared with placebo

A consistent treatment benefit vs placebo was seen across patient subgroups with Tavlesse in the FIT-1 and FIT-2 clinical trials^{2, 3, 5}

Table showing patient subgroups with Tavlesse in the FIT-1 and FIT-2 clinical trials.

Bleeding events and rescue medication

Treatment effect favoured Tavlesse with a trend towards fewer bleeding episodes and less rescue medication use compared with placebo

Bleeding events

Tavlesse patients had a trend towards a lower incidence of bleeding episodes compared to placebo patients^2-4

In the placebo-controlled trials, the incidence of bleeding in patients who received Tavlesse (regardless of responder status) was 29%, compared with 37% in patients who received placebo^2,3

Rescue medication

There was a trend towards Tavlesse patients requiring less rescue medication than placebo patients¹

Of patients treated with Tavlesse in the phase 3 clinical studies (FIT-1 + FIT-2 + FIT-3)^4,*: 67% did not require rescue medication at any visit

^*Compiled from interim analysis. Data cutoff: 8 March 2018.

In the placebo-controlled trials, 30% of patients who received Tavlesse (regardless of responder status) required rescue medication, compared with 45% of patients who received placebo^{2, 3}

ITP: immune thrombocytopenia

References:

Bussel J, Arnold DM, Grossbard E, et al. Fostamatinib for the treatment of adult persistent and chronic immune thrombocytopenia: results of two phase 3, randomized, placebo-controlled trials. Am J Hematol. 2018;93(7):921-930
Tavlesse Summary of Product Characteristics. Great Britain. Grifols. Date of revision: January 2021. Available at https://www.medicines.org.uk/emc/product/11479 . Accessed on 14/2/2022.
Tavlesse Summary of Product Characteristics. Northern Ireland. Grifols. Date of revision: August 2021. Available at https://www.emcmedicines.com/en-gb/northernireland/medicine?id=9c2f7cf0-129d-42a3-a61c-d729ae80e50c. Accessed on 14/2/2022
Bussel J, Arnold DM, Boxer MA, et al. Long-term fostamatinib treatment of adults with immune thrombocytopenia during the phase 3 clinical trial program. Am J Hematol. 2019;94(5):546-553
Boccia R, Boxer MA, Ghanima W, et al. Enhanced responses to fostamatinib as second-line therapy and in persistent immune thrombocytopenia (ITP) patients. Blood. 2019;134(suppl 1):1069. doi:10.1182/blood-2019-1264