Takhzyro

Pharmacotherapeutic group: Other haematological agents, drugs used in hereditary angioedema, ATC code: B06AC05 Mechanism of action Lanadelumab is a fully human, monoclonal antibody (IgG1/ κ-light chain). Lanadelumab inhibits active plasma kallikrein proteolytic activity. Increased plasma kallikrein activity leads to proteolysis of high-molecular-weight-kininogen (HMWK) to generate cleaved HMWK (cHMWK) and bradykinin, which is associated with inflammation and swelling in HAE attacks. Pharmacodynamic effects In adult and adolescent (12 to less than 18 years of age) patients, c oncentration-dependent inhibition of plasma kallikrein, measured as reduction of cHMWK levels, was demonstrated after subcutaneous administration of TAKHZYRO 150 mg every 4 weeks, 300 mg every 4 weeks or 300 mg every 2 weeks in subjects with HAE. The pharmacokinetic-pharmacodynamic (PK-PD) relationship between TAKHZYRO and cHMWK is described by an indirect exposure- response pharmacological model. The cHMWK formation rate was maximally reduced by 53.7% and the TAKHZYRO concentration associated with the 50% Inhibition (IC 50 ) was 5705 ng/ml. For children aged 2 to less than 6 years (150 mg every 4 weeks) and 6 to less than 12 years (150 mg every 2 weeks), the observed mean percent change from baseline in cHMWK levels was similar to that observed in adult and adolescent (12 to less than 18 years of age) patients. Clinical efficacy and safety HELP study The HELP study was a multicenter, randomised, double-blind, placebo-controlled parallel-group study in 125 (115 adults and 10 adolescents) subjects with symptomatic type I or II HAE. Subjects were randomised into 1 of 4 parallel treatment arms, stratified by baseline attack rate, in a 3:2:2:2 ratio (placebo, lanadelumab 150 mg every 4 weeks, lanadelumab 300 mg every 4 weeks, or lanadelumab 300 mg every 2 weeks by subcutaneous injection) for the 26-week treatment period. The median (range) age of the study population was 42 (12 to 73) years with 88 female subjects (70%). A history of laryngeal angioedema attacks was reported in 65% (81/125) of subjects and 56% (70/125) were on prior long-term prophylaxis (LTP). During the study run-in period, the mean attack rate was 3.7 attacks/month with 52% (65/125) of subjects experiencing ≥3 attacks/month. All TAKHZYRO treatment arms produced statistically significant reductions in the mean HAE attack rate compared to placebo across all primary and secondary endpoints in the Intent-to-Treat population (ITT) (Table 3). Table 3. Results of primary and secondary efficacy measures-ITT population Endpoint statistics a Placebo (N=41) Lanadelumab 150 mg every 4 weeks (N=28) 300 mg every 4 weeks (N=29) 300 mg every 2 weeks (N=27) Primary endpoint - Number of HAE attacks from Day 0 to 182 LS Mean (95% CI) monthly attack rate b 1.97 (1.64, 2.36) 0.48 (0.31, 0.73) 0.53 (0.36, 0.77) 0.26 (0.14, 0.46) % Reduction relative to placebo (95% CI) c 76 (61, 85) 73 (59, 82) 87 (76, 93) Adjusted p-values d <0.001 <0.001 <0.001 Secondary endpoint - Number of HAE attacks requiring acute treatment from Day 0 to 182 LS Mean (95% CI) monthly attack rate b 1.64 (1.34, 2.00) 0.31 (0.18, 0.53) 0.42 (0.28, 0.65) 0.21 (0.11, 0.40) % Reduction relative to placebo (95% CI) c 81 (66, 89) 74 (59, 84) 87 (75, 93) Adjusted p-values d <0.001 <0.001 <0.001 Secondary endpoint - Number of moderate or severe HAE attacks from Day 0 to 182 LS Mean (95% CI) monthly attack rate b 1.22 (0.97, 1.52) 0.36 (0.22, 0.58) 0.32 (0.20, 0.53) 0.20 (0.11, 0.39) % Reduction relative to placebo (95% CI) c 70 (50, 83) 73 (54, 84) 83 (67, 92) Adjusted p-values d <0.001 <0.001 <0.001 Note: CI=confidence interval; LS = least squares. a Results are from a Poisson regression model accounting for over dispersion with fixed effects for treatment group (categorical) and normalized baseline attack rate (continuous), and the logarithm of time in days each subject was observed during the treatment period as an offset variable in the model. b Model-based treatment period HAE attack rate (attacks/4 weeks). c % reduction relative to placebo corresponds to 100% * (1-rate ratio). The rate ratio is ratio of the model-based treatment period HAE attack rates. d Adjusted p-values for multiple testing. The mean reduction in HAE attack rate was consistently higher across the TAKHZYRO treatment arms compared to placebo regardless of the baseline history of LTP, laryngeal attacks, or attack rate during the run-in period. The percentage of subjects who were attack free is provided in Table 4. Table 4. Percentage of subjects who were attack free through treatment Criteria Placebo Lanadelumab 150 mg every 4 weeks 300 mg every 4 weeks 300 mg every 2 weeks Treatment period (Day 0 to Day 182, 26 weeks) N 41 28 29 27 Attack free 2% 39% 31% 44% The percentage of patients who were attack free for the last 16-weeks (Day 70 to Day 182) of the study was 77% in the 300 mg every 2 weeks group, compared to 3% of patients in the placebo group. 100% of the subjects on 300 mg every 2 weeks or every 4 weeks and 89% on 150 mg every 4 weeks achieved at least a 50% reduction in HAE attack rate compared to the run-in period. Health related quality of life All TAKHZYRO treatment groups observed an improvement in Angioedema Quality of Life Questionnaire (AE-QoL) total and domain (functioning, fatigue/mood, fear/shame, and nutrition) scores compared to the placebo group; the largest improvement was observed in the functioning score as shown in Table 5. A reduction of 6 points is considered a clinically meaningful improvement. The percentage of patients who achieved a clinically meaningful improvement in AE-QoL total score was 65% (Odds ratio vs placebo, [95% CI]= 3.2 [1.1, 9.2]), 63% (2.9 [1.1, 8.1]), and 81% (7.2 [2.2, 23.4]), in TAKHZYRO 150 mg every 4 weeks, 300 mg every 4 weeks, and 300 mg every 2 weeks groups, respectively, compared to 37% of patients in the placebo group. Table 5. Change in AE-QoL score a - placebo vs TAKHZYRO at week 26 in HELP study LS mean change (SD) from baseline at week 26 Placebo TAKHZYRO total AE-QoL Total score -4.7 (18.8) -19.5 (18.6) Functioning score -5.4 (22.7) -29.3 (22.9) Fatigue/Mood score -1.8 (23.3) -13.0 (23.1) Fear/Shame score -9.0 (24.0) -18.8 (23.7) Nutrition score 0.5 (22.5) -17.0 (22.3) Note: AE-QoL= Angioedema Quality of Life; LS=least squares; SD = standard deviation. a Lower scores indicate lower impairment (or better health-related quality of life). HELP study extension Long-term safety and efficacy, PK, and impact on health-related quality of life (HRQoL) of TAKHZYRO for prophylaxis to prevent HAE attacks were evaluated in an open-label uncontrolled HELP study extension. A total of 212 adult and adolescent (≥ 12 years) subjects with symptomatic type I or II HAE received at least one dose of lanadelumab 300 mg every 2 weeks in this study, including 109 subjects who entered as rollover subjects from the HELP study. Rollover subjects, regardless of randomisation group in the HELP Study, received a single dose of lanadelumab 300 mg at study entry and did not receive additional treatment until the occurrence of an HAE attack. After the first HAE attack, all subjects received open-label treatment with lanadelumab 300 mg every 2 weeks. The study also included 103 new or non-rollover subjects (including 19 subjects from Phase1b study) who had a historical baseline attack rate of ≥ 1 attack per 12 weeks. The non-rollover subjects received lanadelumab 300 mg every 2 weeks at study entry. Subjects were allowed to initiate self-administration after receiving the first 2 doses from a health care professional in clinic and completing appropriate training. The majority of subjects (173/212; 81.6%) who were treated in this study completed at least 30 months of treatment (either as a rollover or non-rollover subjects). The mean (SD) time in the HELP study extension was 29.6 (8.20) months. The majority of subjects self-administered lanadelumab (60.6% of 8,018 injections). There was a sustained reduction in attack rates compared to baseline during the HELP study extension, with a similar response to TAKHZYRO observed in both rollover (92.4%) and non-rollover groups (82.0%) and an overall reduction rate of 87.4%. Though the magnitude of the attack rate reduction in the HELP study limited the potential for further reductions in the HELP extension study, mean attack rates for the rollover subjects decreased further at the time of the final analysis and ranged from 0.08 to 0.26 attacks per month. In addition, the mean (SD) percentage of attack-free days was 97.7 (6.0)% and the mean (SD) duration of the attack-free period was 415.0 (346.1) days. The proportion of patients with a maximum attack-free period of 6 months or more or 12 months or more was 81.8% and 68.9%, respectively. CASPIAN study The CASPIAN study was a multicenter, randomised, double-blind, placebo-controlled study in 77 adult subjects to evaluate the efficacy of lanadelumab in preventing acute attacks of non‑histaminergic angioedema in subjects with normal C1-INH. Of the subjects enrolled, 5 (6.5%) were HAE nC1-INH subjects with known mutations (FXII, PLG), 13 (16.9%) were HAE nC1-INH subjects with a family history of angioedema but who did not have a known mutation, and 59 (76.6%) were subjects with idiopathic non-histaminergic angioedema who did not meet the clinical definition of HAE. No statistically significant treatment effect compared to placebo was observed in any subgroup. Paediatric population SPRING study The safety and efficacy of TAKHZYRO for prophylaxis to prevent HAE attacks in children were evaluated in an open-label, multicenter, Phase 3 SPRING study. Dosing regimens were based on the following pre-defined age groups: children from 2 to less than 6 years of age were to receive lanadelumab 150 mg every 4 weeks and children from 6 to less than 12 years of age were to receive lanadelumab 150 mg every 2 weeks. The overall treatment period was 52 weeks, equally divided into Treatment Period A and B. The study enrolled 21 paediatric subjects who had a baseline attack rate of ≥ 1 attack per 3 months (12 weeks) and a confirmed diagnosis of type I or II HAE. In Treatment Period A, subjects aged 2 to < 6 years (n=4) and 6 to < 12 years (n=17) received lanadelumab 150 mg every 4 weeks and 150 mg every 2 weeks, respectively. The youngest patient included in the study was 3.5 years old. In Treatment Period B, subjects receiving lanadelumab 150 mg every 2 weeks (i.e., subjects 6 to less than 12 years of age) could reduce dosing to 150 mg every 4 weeks if they were well-controlled (e.g., attack free) for 26 weeks with lanadelumab treatment. Seven subjects in the 6 to less than 12 years age group switched to 150 mg every 4 weeks during Treatment Period B, and one subject (enrolled in the 2 to less than 6 years age group) turned 6 years of age during Treatment Period A and switched to 150 mg every 2 weeks during Treatment Period B after experiencing recurrent attacks. The total exposure was 5.5 patient-years in the “every 4 weeks”- dosing regimen group (age range 3.5‑10.4 years) and 14.47 patient-years in the “every 2 weeks”-dosing regimen group (age range 6‑10.9 years). The TAKHZYRO dose regimen in both age groups produced reduction in mean HAE attack rate compared to baseline and an increased percentage of attack-free subjects in Treatment Period A (Table 6). Similar results were observed for the overall, 52-week treatment period. Table 6. Results of efficacy measures Criteria TAKHZYRO 150 mg every 4 weeks a 150 mg every 2 weeks a Total Treatment Period A (26 weeks) N 4 17 21 Baseline attack rate (attacks/month b ), mean (SD) 1.9 (1.0) 1.8 (1.6) 1.8 (1.5) On-treatment attack rate (attacks/month b ), mean (SD) 0.2 (0.3) 0.1 (0.2) 0.1 (0.2) Attack-free subjects, N (%) 3 (75.0) 14 (82.4) 17 (81.0) a The actual treatment received during the given study period. b Month is defined as 28 days. Attack rates at baseline and on-treatment were calculated over the 4-12-week observation period and the 26-week treatment Period A, respectively. Immunogenicity Anti-drug antibodies (ADA) were very commonly detected. No evidence of ADA impact on pharmacokinetics, efficacy or safety was observed.