Caplacizumab

CABLIVI is indicated for the treatment of adult and pediatric patients 12 years of age and older with acquired thrombotic thrombocytopenic purpura (aTTP), in combination with plasma exchange and immunosuppressive therapy. CABLIVI is a von Willebrand factor (vWF)-directed antibody fragment indicated for the treatment of adult and pediatric patients 12 years of age and older with acquired thrombotic thrombocytopenic purpura (aTTP), in combination with plasma exchange and immunosuppressive therapy. ( 1 )

For injection: 11 mg as a white lyophilized powder in a single-dose vial. For injection: 11 mg as a lyophilized powder in a single-dose vial. ( 3 )

CABLIVI is contraindicated in patients with a previous severe hypersensitivity reaction to caplacizumab-yhdp or to any of the excipients. Hypersensitivity reactions have included urticaria [see Adverse Reactions (6.1) ] . Previous severe hypersensitivity reaction to caplacizumab-yhdp or any of the excipients. ( 4 )

5 WARNINGS AND PRECAUTIONS Hemorrhage: Serious and fatal bleeding can occur. Risk of bleeding is increased in patients with underlying coagulopathies or on concomitant antiplatelet agents or anticoagulants. If clinically significant bleeding occurs, interrupt treatment. Withhold CABLIVI 7 days prior to elective surgery, dental procedures, or other invasive interventions. ( 5.1 )

5.1 Hemorrhage CABLIVI increases the risk of bleeding [see Adverse Reactions (6.1) ] . In clinical studies, severe bleeding adverse reactions of epistaxis, gingival bleeding, upper gastrointestinal hemorrhage, and metrorrhagia were each reported in 1% of subjects. Overall, bleeding events occurred in approximately 58% of patients on CABLIVI versus 43% of patients on placebo. In the postmarketing setting, cases of life-threatening and fatal bleeding were reported in patients receiving CABLIVI. The risk of bleeding is increased in patients with underlying coagulopathies (e.g., hemophilia, other coagulation factor deficiencies). It is also increased with concomitant use of CABLIVI with drugs affecting hemostasis and coagulation [see Drug Interactions (7) and Clinical Pharmacology (12.3) ] . Avoid concomitant use of CABLIVI with antiplatelet agents, thrombolytic drugs, heparin, or anticoagulants. Interrupt use of CABLIVI if clinically significant bleeding occurs. If needed, von Willebrand factor concentrate may be administered to rapidly correct hemostasis. If CABLIVI is restarted, monitor closely for signs of bleeding. Withhold CABLIVI for 7 days prior to elective surgery, dental procedures or other invasive interventions. If emergency surgery is needed, the use of von Willebrand factor concentrate may be considered to correct hemostasis. After the risk of surgical bleeding has resolved, and CABLIVI is resumed, monitor closely for signs of bleeding.

Concomitant use of anticoagulants or antiplatelet agents with CABLIVI may increase the risk of bleeding. Monitor closely for bleeding with concomitant use. ( 7 ) Concomitant Use of Anticoagulants, Thrombolytic Drugs, Heparin or Antiplatelet Agents Concomitant use of CABLIVI with any anticoagulant, thrombolytic drugs, heparin or antiplatelet agent may increase the risk of bleeding. Avoid concomitant use when possible. Assess and monitor closely for bleeding with concomitant use [see Warnings and Precautions (5.1) and Clinical Pharmacology (12.3) ] .

The following clinically significant adverse reactions are also discussed in other sections of the labeling: Hemorrhage [see Warnings and Precautions (5.1) ] In adults, the most common adverse reactions (incidence >15%) are epistaxis, headache, and gingival bleeding. In pediatric patients, the most frequently reported adverse reactions are epistaxis and tachycardia. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Ablynx US at 1-800-745-4447 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. TITAN and HERCULES The safety of CABLIVI was evaluated in two placebo-controlled clinical studies (HERCULES, in which 71 patients received CABLIVI; and TITAN, in which 35 patients received CABLIVI). The data described below and in the Warnings and Precautions reflect exposure to CABLIVI during the blinded periods of both studies, which include 106 patients with aTTP who received at least one dose, age 18 to 79 years, of whom 69% were female and 73% were White. The median treatment duration with CABLIVI was 35 days (range 1–77 days). The most frequently reported adverse reactions (>15%) were epistaxis, headache and gingival bleeding. Seven patients (7%) in the CABLIVI group experienced an adverse reaction leading to study drug discontinuation. None of the adverse reactions leading to discontinuation were observed in more than 1% of patients. Among 106 patients treated with CABLIVI during the TITAN and HERCULES studies, serious bleeding adverse reactions reported in ≥2% patients included epistaxis (4%) and subarachnoid hemorrhage (2%). Adverse reactions that occurred in ≥2% of patients treated with CABLIVI and more frequently than in those treated with placebo across the pooled data from the two trials are summarized in Table 1. Urticaria was seen during plasma exchange. Table 1: Adverse Reactions in ≥2% of Patients Treated with CABLIVI and More Frequent than Placebo During the Blinded Periods of aTTP Studies (HERCULES and TITAN) Adverse Reaction by Body System CABLIVI (N=106) n (%) Placebo (N=110) n (%) Gastrointestinal disorders Gingival bleeding 17 (16) 3 (3) Rectal hemorrhage 4 (4) 0 (0) Abdominal wall hematoma 3 (3) 1 (1) General disorders and administration site conditions Fatigue 16 (15) 10 (9) Pyrexia 14 (13) 12 (11) Injection site hemorrhage 6 (6) 1 (1) Catheter site hemorrhage 6 (6) 5 (5) Injection site pruritus 3 (3) 0 (0) Musculoskeletal and connective tissue disorders Back pain 7 (7) 4 (4) Myalgia 6 (6) 2 (2) Nervous system disorders Headache 22 (21) 15 (14) Paresthesia 13 (12) 11 (10) Renal and urinary disorders Urinary tract infection 6 (6) 4 (4) Hematuria 4 (4) 3 (3) Reproductive system and breast disorders Vaginal hemorrhage 5 (5) 2 (2) Menorrhagia 4 (4) 1 (1) Respiratory, thoracic and mediastinal disorders Epistaxis 31 (29) 6 (6) Dyspnea 10 (9) 5 (5) Skin and subcutaneous tissue disorders Urticaria 15 (14) 7 (6) Pediatric Patients The safety of CABLIVI in patients aged ≤18 years with aTTP was evaluated in an observational, retrospective chart review (OBS17325) [see Clinical Studies (14) ] . The most commonly reported events were epistaxis in 4 (13.3%) patients and tachycardia in 4 (13.3%) patients. One serious bleeding adverse reaction (hemorrhage urinary tract) was reported. The adverse reaction profile in pediatric patients 12 years and older with aTTP was consistent with that in adults.

6.3 Postmarketing Experience The following adverse reactions have been identified during postapproval use of CABLIVI. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to caplacizumab-yhdp exposure. General disorders and administration site conditions: Injection site reactions including injection site pain, injection site bruising and injection site erythema

In case of overdose, based on the pharmacological action of CABLIVI, there is the potential for an increased risk of bleeding [see Warnings and Precautions (5.1) ] . Monitor patients for signs and symptoms of bleeding if overdose occurs. Consider the use of von Willebrand factor concentrate to correct hemostasis, if needed.

8.1 Pregnancy Risk Summary There are no available data on CABLIVI use in pregnant women to inform a drug-associated risk of major birth defects and miscarriage. However, there are potential risks of hemorrhage in the mother and fetus associated with use of CABLIVI (see Clinical Considerations ) . In animal reproduction studies, there was no evidence of adverse developmental outcomes with intramuscular administration of caplacizumab-yhdp during organogenesis in guinea pigs at exposures approximately 30 times the AUC in humans at the recommended subcutaneous injection dose of 11 mg (see Data ) . All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. The background rate of major birth defects and miscarriage in the indicated population is unknown. In the U.S. general population, the estimated background rate of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Clinical Considerations Fetal/neonatal adverse reactions CABLIVI may increase the risk of bleeding in the fetus and neonate. Monitor neonates for bleeding [see Warnings and Precautions (5.1) ] . Maternal adverse reactions All patients receiving CABLIVI, including pregnant women, are at risk for bleeding. Pregnant women receiving CABLIVI should be carefully monitored for evidence of excessive bleeding [see Warnings and Precautions (5.1) ] . Data Animal data Two separate reproduction studies were conducted in pregnant guinea pigs with administration of caplacizumab-yhdp during the organogenesis period. In an embryo-fetal development study, caplacizumab-yhdp was administered intramuscularly at doses up to 20 mg/kg/day from gestational day (GD) 6 to GD 41 in guinea pigs. No maternal toxicity or adverse developmental outcomes were observed. In a toxicokinetic study assessing the exposure of caplacizumab-yhdp in the dams and fetuses, caplacizumab-yhdp was administered once daily to female guinea pigs at doses up to 40 mg/kg/day (corresponding to a drug exposure of approximately 30 times the AUC in humans at the recommended dose of 11 mg) by intramuscular injection from GD 6 to GD 41 or GD 61. Exposure to caplacizumab-yhdp was observed in the dams and fetuses, with no effects on embryo-fetal development.

8.2 Lactation Risk Summary There is no information regarding the presence of caplacizumab-yhdp in human milk, the effects on the breastfed child or the effects on milk production. The developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for CABLIVI and any potential adverse effects on the breastfed child from CABLIVI, or from the underlying maternal condition.

8.4 Pediatric Use The safety and effectiveness of CABLIVI in pediatric patients 12 years of age and older with acquired thrombotic thrombocytopenic purpura (aTTP), in combination with plasma exchange and immunosuppressive therapy have been established. Use of CABLIVI for this indication is supported by evidence from an observational, retrospective chart review and pharmacokinetic/pharmacodynamic modeling and simulation data [see Adverse Reactions (6) , Clinical Pharmacology (12.3) and Clinical Studies (14) ] . The safety and effectiveness of CABLIVI in pediatric patients less than 12 years of age have not been established.

8.5 Geriatric Use Clinical studies of CABLIVI did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects.

8.6 Hepatic Impairment No formal studies with CABLIVI have been conducted in patients with severe acute or chronic hepatic impairment and no data regarding the use of CABLIVI in these populations are available. Due to a potential increased risk of bleeding, use of CABLIVI in patients with severe hepatic impairment requires close monitoring for bleeding [see Warnings and Precautions (5.1) ] .

Risk Summary There are no available data on CABLIVI use in pregnant women to inform a drug-associated risk of major birth defects and miscarriage. However, there are potential risks of hemorrhage in the mother and fetus associated with use of CABLIVI (see Clinical Considerations ) . In animal reproduction studies, there was no evidence of adverse developmental outcomes with intramuscular administration of caplacizumab-yhdp during organogenesis in guinea pigs at exposures approximately 30 times the AUC in humans at the recommended subcutaneous injection dose of 11 mg (see Data ) . All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. The background rate of major birth defects and miscarriage in the indicated population is unknown. In the U.S. general population, the estimated background rate of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Clinical Considerations Fetal/neonatal adverse reactions CABLIVI may increase the risk of bleeding in the fetus and neonate. Monitor neonates for bleeding [see Warnings and Precautions (5.1) ] . Maternal adverse reactions All patients receiving CABLIVI, including pregnant women, are at risk for bleeding. Pregnant women receiving CABLIVI should be carefully monitored for evidence of excessive bleeding [see Warnings and Precautions (5.1) ] . Data Animal data Two separate reproduction studies were conducted in pregnant guinea pigs with administration of caplacizumab-yhdp during the organogenesis period. In an embryo-fetal development study, caplacizumab-yhdp was administered intramuscularly at doses up to 20 mg/kg/day from gestational day (GD) 6 to GD 41 in guinea pigs. No maternal toxicity or adverse developmental outcomes were observed. In a toxicokinetic study assessing the exposure of caplacizumab-yhdp in the dams and fetuses, caplacizumab-yhdp was administered once daily to female guinea pigs at doses up to 40 mg/kg/day (corresponding to a drug exposure of approximately 30 times the AUC in humans at the recommended dose of 11 mg) by intramuscular injection from GD 6 to GD 41 or GD 61. Exposure to caplacizumab-yhdp was observed in the dams and fetuses, with no effects on embryo-fetal development.

The safety and effectiveness of CABLIVI in pediatric patients 12 years of age and older with acquired thrombotic thrombocytopenic purpura (aTTP), in combination with plasma exchange and immunosuppressive therapy have been established. Use of CABLIVI for this indication is supported by evidence from an observational, retrospective chart review and pharmacokinetic/pharmacodynamic modeling and simulation data [see Adverse Reactions (6) , Clinical Pharmacology (12.3) and Clinical Studies (14) ] . The safety and effectiveness of CABLIVI in pediatric patients less than 12 years of age have not been established.

Clinical studies of CABLIVI did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects.

Caplacizumab-yhdp is a von Willebrand factor (vWF)-directed antibody fragment that consists of two identical humanized building blocks, linked by a three-alanine linker. Caplacizumab-yhdp is produced in Escherichia coli by recombinant DNA technology and has an approximate molecular weight of 28 kDa. CABLIVI (caplacizumab-yhdp) for injection is a sterile, white, preservative-free, lyophilized powder. Each single-dose vial delivers 11 mg caplacizumab-yhdp, anhydrous citric acid (0.18 mg), polysorbate 80 (0.10 mg), sucrose (62 mg), and trisodium citrate dihydrate (4.91 mg). After reconstitution with 1 mL of Sterile Water for Injection, USP, the final concentration is 11 mg/mL, at a pH of approximately 6.5.

12.1 Mechanism of Action Caplacizumab-yhdp targets the A1-domain of vWF, and inhibits the interaction between vWF and platelets, thereby reducing both vWF-mediated platelet adhesion and platelet consumption.

12.2 Pharmacodynamics Ristocetin cofactor (RICO) activity was used to assess vWF activity. Subcutaneous doses of caplacizumab-yhdp at greater than or equal to the approved recommended dosage to healthy subjects and patients with aTTP decreased RICO activity levels to below 20% approximately 4 hours post-dose. RICO activity returned to baseline values within 7 days of drug discontinuation. Caplacizumab-yhdp decreased vWF antigen and factor VIII:C levels. These reductions were transient and returned to baseline upon cessation of treatment.

12.3 Pharmacokinetics Caplacizumab-yhdp pharmacokinetics depends on the expression of the target vWF and are not dose proportional. Higher levels of vWF antigen increase the fraction of drug-target complex retained in the circulation. Steady-state was reached following the first administration of CABLIVI in healthy subjects, with minimal accumulation. Following a single subcutaneous dose of 10 mg caplacizumab-yhdp to healthy subjects the mean (CV%) peak concentration (C max ) was 528 (20%) ng/mL and AUC 0–24 was 7951 (16%). Following subcutaneous dosing of 10 mg caplacizumab-yhdp daily for 14 days to healthy subjects, the mean (CV%) C max was 348 (30%) ng/mL and AUC 0–τ was 6808 (26%) hr∙ng/mL. Absorption The bioavailability of subcutaneous caplacizumab-yhdp is approximately 90%. The maximum concentration was observed 6 to 7 hours after subcutaneous dosing of 10 mg caplacizumab-yhdp once daily in healthy subjects. Distribution Caplacizumab-yhdp central volume of distribution is 6.33 L in patients with aTTP. Elimination The half-life of caplacizumab-yhdp is concentration and target-level dependent. Metabolism The available data suggest target-bound caplacizumab-yhdp is metabolized within the liver. Because caplacizumab-yhdp is a monoclonal antibody fragment, it is expected to be catabolized by various proteolytic enzymes. Excretion The available nonclinical data suggest unbound caplacizumab-yhdp is cleared renally. Antidrug Antibodies No clinically significant differences in the pharmacokinetics of caplacizumab-yhdp were observed in patients with pre-existing or treatment-emergent anti-drug antibodies. Specific Populations No clinically significant differences in the pharmacokinetics of caplacizumab-yhdp were observed based on age (18 to 79 years), sex (66% females), race (White [83%] and Black [17%]), blood group (O [41%] and other groups [59%]), or renal impairment (mild [CrCl: 60 to 90 mL/min], moderate [CrCl: 30 to 60 mL/min] or severe [CrCl: 15 to 30 mL/min]). The effect of hepatic impairment on the pharmacokinetics of caplacizumab-yhdp is unknown [see Use in Specific Populations (8.6) ] . Pediatric population A pharmacokinetic-pharmacodynamic (PK/PD) population model was developed using clinical data from adult populations following intravenous and subcutaneous administration of caplacizumab-yhdp. Simulations performed based on this PK/PD model showed that the predicted caplacizumab-yhdp exposure and suppression of von Willebrand factor antigen (vWF:Ag) are similar in pediatric patients ≥12 years of age to those in adults when the adult dose (11 mg/day) is used in children. Drug Interaction Studies No dedicated drug-drug interaction studies with caplacizumab-yhdp have been conducted.

12.6 Immunogenicity The observed incidence of anti-drug antibodies is highly dependent on the sensitivity and specificity of the assay. Differences in assay methods preclude meaningful comparisons of the incidence of anti-drug antibodies in the studies described below with the incidence of anti-drug antibodies in other studies, including those of caplacizumab-yhdp. The prevalence of pre-existing antibodies binding to caplacizumab-yhdp observed during clinical studies and during evaluation of commercially available human samples varied between 4% and 63%. In aTTP patients, pre-existing antibodies can be produced by the patient or can originate from donor plasma during plasma exchange. No clinically apparent impact of these pre-existing antibodies on clinical efficacy or safety was found. Treatment-emergent anti-drug antibodies (TE ADA) against caplacizumab-yhdp were detected in 3% of patients treated with CABLIVI in the HERCULES study. In the HERCULES study, TE ADA were further characterized as having neutralizing potential. There was no clinically apparent impact on clinical efficacy or safety.

Caplacizumab-yhdp targets the A1-domain of vWF, and inhibits the interaction between vWF and platelets, thereby reducing both vWF-mediated platelet adhesion and platelet consumption.

Ristocetin cofactor (RICO) activity was used to assess vWF activity. Subcutaneous doses of caplacizumab-yhdp at greater than or equal to the approved recommended dosage to healthy subjects and patients with aTTP decreased RICO activity levels to below 20% approximately 4 hours post-dose. RICO activity returned to baseline values within 7 days of drug discontinuation. Caplacizumab-yhdp decreased vWF antigen and factor VIII:C levels. These reductions were transient and returned to baseline upon cessation of treatment.

Caplacizumab-yhdp pharmacokinetics depends on the expression of the target vWF and are not dose proportional. Higher levels of vWF antigen increase the fraction of drug-target complex retained in the circulation. Steady-state was reached following the first administration of CABLIVI in healthy subjects, with minimal accumulation. Following a single subcutaneous dose of 10 mg caplacizumab-yhdp to healthy subjects the mean (CV%) peak concentration (C max ) was 528 (20%) ng/mL and AUC 0–24 was 7951 (16%). Following subcutaneous dosing of 10 mg caplacizumab-yhdp daily for 14 days to healthy subjects, the mean (CV%) C max was 348 (30%) ng/mL and AUC 0–τ was 6808 (26%) hr∙ng/mL. Absorption The bioavailability of subcutaneous caplacizumab-yhdp is approximately 90%. The maximum concentration was observed 6 to 7 hours after subcutaneous dosing of 10 mg caplacizumab-yhdp once daily in healthy subjects. Distribution Caplacizumab-yhdp central volume of distribution is 6.33 L in patients with aTTP. Elimination The half-life of caplacizumab-yhdp is concentration and target-level dependent. Metabolism The available data suggest target-bound caplacizumab-yhdp is metabolized within the liver. Because caplacizumab-yhdp is a monoclonal antibody fragment, it is expected to be catabolized by various proteolytic enzymes. Excretion The available nonclinical data suggest unbound caplacizumab-yhdp is cleared renally. Antidrug Antibodies No clinically significant differences in the pharmacokinetics of caplacizumab-yhdp were observed in patients with pre-existing or treatment-emergent anti-drug antibodies. Specific Populations No clinically significant differences in the pharmacokinetics of caplacizumab-yhdp were observed based on age (18 to 79 years), sex (66% females), race (White [83%] and Black [17%]), blood group (O [41%] and other groups [59%]), or renal impairment (mild [CrCl: 60 to 90 mL/min], moderate [CrCl: 30 to 60 mL/min] or severe [CrCl: 15 to 30 mL/min]). The effect of hepatic impairment on the pharmacokinetics of caplacizumab-yhdp is unknown [see Use in Specific Populations (8.6) ] . Pediatric population A pharmacokinetic-pharmacodynamic (PK/PD) population model was developed using clinical data from adult populations following intravenous and subcutaneous administration of caplacizumab-yhdp. Simulations performed based on this PK/PD model showed that the predicted caplacizumab-yhdp exposure and suppression of von Willebrand factor antigen (vWF:Ag) are similar in pediatric patients ≥12 years of age to those in adults when the adult dose (11 mg/day) is used in children. Drug Interaction Studies No dedicated drug-drug interaction studies with caplacizumab-yhdp have been conducted.

, Mutagenesis, Impairment of Fertility No studies have been performed to evaluate the potential of caplacizumab-yhdp for carcinogenicity or genotoxicity. Animal reproduction studies assessing the effects of caplacizumab-yhdp on male and female fertility have not been conducted.

17 PATIENT COUNSELING INFORMATION Advise the patient to read the FDA-approved patient labeling (Instructions for Use). Bleeding [see Warnings and Precautions (5.1) ] Advise patients and/or caregivers that bruising and bleeding may occur more easily, that nose bleeds and bleeding of gums may occur, and that it may take them longer than usual to stop bleeding. Advise patients and/or caregivers to contact their healthcare provider immediately if symptoms of excessive bruising, excessive bleeding, or major bleeding occur. Signs and symptoms of bleeding include pain, swelling or discomfort, prolonged bleeding from cuts, increased menstrual flow or vaginal bleeding, nosebleeds, bleeding of gums from brushing, unusual bleeding or bruising, red or dark brown urine, red or tar black stools, headache, dizziness, or weakness [see Warnings and Precautions (5.1) ] . Advise patients and/or caregivers to inform their healthcare provider before scheduling any elective surgery, dental procedure or other invasive interventions.

16.2 Storage Store refrigerated at 2°C to 8°C (36°F to 46°F) in the original carton to protect from light. Do not freeze. Unopened vials may be stored in the original carton at room temperature up to 30°C (86°F) for a single period of up to 2 months. Do not return CABLIVI to the refrigerator after it has been stored at room temperature.