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

Adapted from Bussel J, et al. 20182, 3
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
Overall response rates achieved in the 24-week evaluation period (double-blind, placebo-controlled trial)1

Adapted from Bussel J, et al. 20182, 3
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
Tavlesse overall response summary – day 1 to 24 weeks1
Median platelet counts by study visit - overall responders (pooled FIT + FIT2)

Adapted from Bussel J, et al. 2018
Study visits (weeks) | 0 | 2 | 4 | 6 | 8 | 10 | 12 | 14 | 16 | 18 | 20 | 22 | 24 |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Overall responders |
43 |
38 |
41 |
40 |
40 |
38 |
37 |
31 |
27 |
26 |
23 |
21 |
20 |
Non-responders |
58 |
48 |
45 |
41 |
40 |
39 |
42 |
7 |
7 |
5 |
4 |
3 |
4 |
Placebo |
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 study2,3
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)

Adapted from Data on file, Grifols
- 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
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 trials2, 3, 5

*Post hoc subgroup. CI: confidence interval; TPO-RA: thrombopoietin-receptor agonists. Overall responder population: Platelet count ≥50,000/μL at least once during first 3 months without need for rescue treatment.¹ Adapted from Bussel J, et al. 20181
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 patients2-4

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 placebo2,3
Rescue medication
There was a trend towards Tavlesse patients requiring less rescue medication than placebo patients1

Adapted from Bussel J, et al. 20181
- 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
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 placebo2, 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