Crisantaspase: prescribing information – dosing, contraindications, interactions, side effects

Enrylaze is indicated as a component of a multi-agent chemotherapeutic regimen for the treatment of acute lymphoblastic leukaemia (ALL) and lymphoblastic lymphoma (LBL) in adult and paediatric patients (1 month and older) who developed hypersensitivity or silent inactivation to E. coli-derived asparaginase.

Enrylaze should be prescribed and administered by physicians and healthcare personnel experienced in the use of antineoplastic products. Appropriate resuscitation equipment and other agents necessary to treat anaphylaxis should be available when administering Enrylaze.

Posology
The recommended dose of Enrylaze is:
- Every 48 hours
- 25 mg/m2 intramuscularly or intravenously

Or
- Monday/Wednesday/Friday
- 25 mg/m2 intramuscularly on Monday and Wednesday, and 50 mg/m2 intramuscularly on Friday; or
- 25 mg/m2 intravenously on Monday and Wednesday, and 50 mg/m2 intramuscularly on Friday; or
- 25 mg/m2 intravenously on Monday and Wednesday, and 50 mg/m2 intravenously on
Friday
Recommended premedication
A consideration to premedicate patients with paracetamol, an H1 receptor blocker, and an H2 receptor blocker 30–60 minutes prior to administration should be made when Enrylaze is being given intravenously to decrease the risk and severity of infusion related reaction/hypersensitivity reaction.

Recommended monitoring
Asparaginase activity can vary between individuals, therefore trough SAA should be monitored. When administered every 48 hours a trough asparaginase activity measurement should be performed at 48 hours post dose. When dosing on a Monday/Wednesday/Friday schedule, trough SAA should be measured 72 hours after the Friday dose and prior to administration of the following Monday dose.
The dosing schedule or route of administration should then be individually adapted (see section 4.4).

Therapy can be further adjusted according to local treatment protocols.

The dose of Enrylaze is administered in mg/m2 and is not administered in units/m2, as used for other asparaginase preparations. Enrylaze is not interchangeable with other crisantaspase products to complete a cycle of treatment.

Special populations
Hepatic impairment
Dose adjustment is not required for patients that develop total bilirubin ≤ 3 times the Upper Limit of Normal (ULN) during treatment.

Enrylaze should be withheld if total bilirubin is > 3 times to ≤ 10 times the ULN during treatment, treatment can continue once resolved. In the event of a severe occurrence (total bilirubin > 10 times the ULN), treatment should be stopped and patients not rechallenged (see section 4.4).

Dose adjustment is not required for patients with pre-existing mild or moderate hepatic impairment (total bilirubin > 1 to 3 times the ULN or AST greater than the ULN). There are insufficient data in patients with pre-existing severe hepatic impairment to support a dose recommendation.

Renal impairment
There are insufficient data in patients with mild, moderate or severe renal impairment to support a dose recommendation.

Paediatric population
No dose adjustment is required in paediatric patients.

The safety and efficacy of children aged younger than 1 month has not yet been established.

Elderly
No dose adjustment is required in elderly patients.

Method of administration
Enrylaze is for intramuscular and/or intravenous use.

For intramuscular use, limit the volume of Enrylaze at a single injection site to 2 mL for patients with a body surface area (BSA) > 0.5 m2, for patients with a BSA < 0.5 m2 limit the volume to 1 mL. If the volume to be administered is greater than the mentioned limits, use multiple injection sites.

For intravenous infusion, it is recommended to administer the dose over 2 hours.

For instructions on dilution of the medicinal product before intravenous administration, see section 6.6.

• History of severe hypersensitivity reactions to the active substance
• Hypersensitivity to any of the excipients listed in section 6.1
• Severe pancreatitis
• History of severe pancreatitis during previous asparaginase therapy
• Severe thrombosis during previous asparaginase therapy
• Severe haemorrhagic events during previous asparaginase therapy

Summary of the safety profile
Serious adverse reactions occurred in 59% of patients who received Enrylaze in a clinical trial. The most frequent serious adverse reactions were febrile neutropenia (29%), pyrexia (10%), vomiting (8%), sepsis (7%), medicinal product hypersensitivity (6%), nausea (6%), and pancreatitis (5%).

The most common adverse reactions were anaemia (52%), vomiting (49%), thrombocytopenia (42%), neutropenia (41%), nausea (38%), febrile neutropenia (32%), fatigue (32%), pyrexia (32%), decreased appetite (29%), transaminase increased (29%), abdominal pain (27%), white blood cell count decreased (27%), headache (25%), diarrhoea (22%), and lymphocyte count decreased (20%).

Tabulated list of adverse reactions
Adverse reactions reported in clinical trial are listed in Table 1 by system organ class and by frequency. The frequencies identified are from patients (n=228) who received 6 doses of Enrylaze, along with a multi-agent chemotherapeutic regimen. Certain adverse reactions listed below, such as reactions resulting from bone marrow suppression, and infections, are known to be associated with multi-agent chemotherapeutic regimens, and the contributory role of Enrylaze is not clear. In individual cases of adverse reactions, other medicinal products of the regimen may have contributed.

Frequencies are defined as: very common (≥ 1/10); common (≥ 1/100 to < 1/10); uncommon (≥ 1/1 000 to < 1/100); rare (≥ 1/10 000 to < 1/1 000); not known (cannot be estimated from the available data). Within each frequency grouping, adverse reactions are presented in order of decreasing seriousness.

Table 1: Adverse reactions in patients receiving Enrylaze with multi-agent chemotherapy (Study JZP458-201)

System organ class
Frequency
Adverse reaction
Infections and infestations
Common
Sepsis
Blood and lymphatic system disorders
Very common
Anaemia, Thrombocytopenia,
Neutropenia, Febrile neutropenia
Immune system disorders
Very common
Drug hypersensitivity
Common
Anaphylactic reaction,
Hypersensitivity
Metabolism and nutrition disorders
Very common
Decreased appetite,
Hyperglycaemia,
Hypoalbuminemia
Common
Hypertriglyceridemia,
Hypoglycaemia,
Hyperammonaemia
Psychiatric disorders
Very common
Anxiety
Common
Irritability
Nervous system disorders
Very common
Headache
Common
Dizziness
Uncommon
Superior sagittal sinus thrombosis
Vascular disorders
Common
Hypotension
Uncommon
Jugular vein thrombosis, Deep vein thrombosis
Respiratory, thoracic and mediastinal disorders
Common
Pulmonary embolism
Gastrointestinal disorders
Very common
Vomiting, Nausea, Abdominal pain, Diarrhoea
Common
Pancreatitis
Skin and subcutaneous tissue disorders
Common
Rash maculo-papular, Pruritus,
Rash, Urticaria, Rash erythematous,
Musculoskeletal and connective tissue disorders
Very common
Pain in extremity
General disorders and administration site conditions
Very common
Fatigue, Pyrexia
Common
Injection site pain, Injection site reaction

Investigations
Very common
Transaminases increased, White blood cell count decreased,
Lymphocyte count decreased,
Weight decreased, Blood bilirubin increased
Common
Blood creatinine increased,
Activated partial thromboplastin time prolonged, Blood fibrinogen decreased,
Antithrombin III decreased
Injury, poisoning and procedural complications
Very common
Contusion
Common
Infusion-related reaction

Description of selected adverse reactions
Hypersensitivity
Hypersensitivity reactions were reported adverse reactions in the Enrylaze clinical trial. The incidence of medicinal product hypersensitivity was 11% and it was severe in 8% of patients. The incidence of anaphylactic reaction was 2%, and it was severe in all patients. Overall hypersensitivity reactions observed more frequently in patients who received Enrylaze intravenously. The frequency of hypersensitivity reactions leading to discontinuation was 10% (see section 4.4).

Pancreatitis
Cases of pancreatitis including life threatening cases have been reported in the Enrylaze clinical trial.
The incidence of pancreatitis was 7%; the incidence of serious events of pancreatitis was 5%; the incidence of life-threatening pancreatitis was 1%. One patient developed pancreatic pseudocyst after acute pancreatitis, which resolved without sequelae. The frequency of pancreatitis in Study JZP458-201 which led to discontinuation was 5% (see section 4.4).

Adults and other special populations
Although the safety profile of adults above 25 years of age has not been studied, some adverse reactions, such as hepatotoxicity, thrombosis, and pancreatitis, have been reported more frequently in adults with acute lymphoblastic leukemia receiving other asparaginases than in paediatric patients.

Immunogenicity
It has been reported that there is no to little cross reactivity between crisantaspase and other E. coli derived asparaginase.

As with all therapeutic proteins, there is a potential for immunogenicity. Immunogenicity assays are highly dependent on the sensitivity and specificity of the assay and may be influenced by several factors such as assay methodology, sample handling, timing of sample collection, concomitant treatment, and underlying disease. For these reasons, comparison of the incidence of antibodies to Enrylaze with the incidence of antibodies to other products may be misleading.

Analysis of patients receiving Enrylaze by either intramuscular injection (n=167) or intravenous infusion (n=61) showed that 116 of 228 (51%) patients had confirmed positive anti-drug antibodies (ADA) toward Enrylaze, 8 (7%) of these were ADA positive at pre dose 1.

A total of 23 (20%) patients who had ADAs experienced hypersensitivity reactions of which 6 (5%) had neutralising antibodies. Of the negative ADA patients 7/112 (6%) experienced a hypersensitivity reaction.

During the course of treatment 73 (63%) patients became ADA negative at least once.

Intravenous infusion
- A total of 34 (56%) patients were found to be ADA positive.
- 1 patient was ADA positive at pre dose 1.
- 33 patients developed ADA toward Enrylaze following administration of Enrylaze. 18 of these patients subsequently became ADA negative at least once during the study.
- 12 (35%) experienced hypersensitivity reactions during the study, and of these patients 2 had neutralising antibodies. Of the negative ADA patients 4/27 (15%) experienced a hypersensitivity reaction.

Intramuscular injection
- A total of 82 (49%) patients were found to be ADA positive.
- 7 patients were ADA positive at pre dose 1.
- 75 patients developed ADA toward Enrylaze following administration of Enrylaze. 55 of these patients subsequently became ADA negative at least once during the study.
- 11 (13%) patients experienced hypersensitivity reactions, and of these patients 4 had neutralising antibodies. Of the negative ADA positive patients 7/85 (8%) experienced a hypersensitivity reaction.

The presence of ADA does not appear to correlate with the occurrence of hypersensitivity reactions.
SAA levels were not impacted for applicable ADA positive patients as they maintained SAA levels ≥ 0.1 U/mL at all available 48- and 72-hour time points during Course 1. No impact on the pharmacokinetics of Enrylaze was observed and ADA status was not found to be a significant factor in population pharmacokinetic analysis.

Paediatric population
The majority of the patients in Study JZP458-201 were children < 18 years old 197/228 (86%) and therefore a comparison of frequency and severity in adverse reactions versus other age groups is not suitable.

Reporting of suspected adverse reactions
Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the national reporting system listed in Appendix V.

Traceability
In order to improve the traceability of biological medicinal products, the name and the batch number of the administered product should be clearly recorded.

Clinical monitoring
Asparaginase activity
SAA varies substantially between patients, when treatment is administered intravenously. The optimal SAA level is ≥ 0.1 U/mL; if this is not observed the dosing schedule should be individually adapted.
When administering Enrylaze intravenously on a Monday/Wednesday/Friday schedule, trough SAA levels should be measured 72 hours after the Friday dose and prior to the following Monday administration. If SAA levels ≥ 0.1 U/mL are not observed, administration of intramuscular Enrylaze or switching to a 48-hour dosing interval (intravenous or intramuscular) should be considered. If SAA levels are monitored at 48-hour intervals of intravenous Enrylaze administration and SAA levels ≥ 0.1 U/mL are not observed, administration intramuscularly should be considered (see section 4.2).

Hypersensitivity reactions
Grade 3 and 4 hypersensitivity reactions after the use of Enrylaze have occurred in patients during clinical trials (see sections 4.3 and 4.8). Hypersensitivity reactions may occur more frequently when treatment is administered intravenously in comparison to when treatment is administered intramuscularly.

Because of the risk of serious allergic reactions, Enrylaze should be administered in a setting with resuscitation equipment and other agents necessary to treat anaphylaxis. Enrylaze should be discontinued in patients with severe hypersensitivity reactions (see section 4.3).

Pancreatitis
Pancreatitis has been reported in patients treated with Enrylaze in clinical trials (see section 4.8).
Patients with symptoms compatible with pancreatitis should be evaluated to establish a diagnosis.

Enrylaze should be discontinued in patients that develop necrotising or haemorrhagic pancreatitis.

In the case of elevations in lipase or amylase > 2 times the ULN or symptomatic pancreatitis, Enrylaze should be withheld until the ULN and symptoms subside. After resolution of pancreatitis, treatment with Enrylaze may be resumed.

Glucose intolerance
Cases of glucose intolerance have been reported in patients receiving Enrylaze in clinical trials (see section 4.8). Glucose levels in patients should be monitored at baseline and periodically during treatment. Insulin therapy should be administered as necessary in patients with hyperglycaemia.

Coagulation disorders
Thrombotic and bleeding events, including sagittal sinus thrombosis and pulmonary embolism have been reported with L-asparaginase therapy. Enrylaze treatment should be held for a thrombotic or haemorrhagic event until symptoms resolve; after resolution, treatment with Enrylaze may be resumed.

Hepatotoxicity
Therapy that includes Enrylaze can cause hepatotoxicity as experienced during clinical trials (see section 4.8).

Patients should be monitored for signs and symptoms of hepatotoxicity. Bilirubin and transaminases should be monitored prior to treatment and as clinically required during treatment with Enrylaze. In the event of severe liver toxicity, treatment with Enrylaze must be discontinued and supportive care provided.

Neurotoxicity
Central nervous system (CNS) toxicity, including encephalopathy, seizures and CNS depression as well as posterior reversible encephalopathy syndrome (PRES) may occur during treatment with any asparaginase therapy.

PRES may occur rarely during treatment with any asparaginase. This syndrome is characterised in magnetic resonance imaging (MRI) by reversible (from a few days to months) lesions/oedema, primarily in the posterior region of the brain. Symptoms of PRES essentially include elevated blood pressure, seizures, headaches, changes in mental state and acute visual impairment (primarily cortical blindness or homonymous hemianopsia).

It is unclear whether the PRES is caused by asparaginase, concomitant treatment or the underlying diseases. PRES is treated symptomatically, including measures to treat any seizures. Discontinuation or dose reduction of concomitantly administered immunosuppressive medicinal products may be necessary. Expert advice should be sought.

Contraception
Contraception should be used during treatment and for 3 months after receiving the final dose of Enrylaze. Women should also undergo pregnancy testing before therapy with Enrylaze is initiated.
Since an indirect interaction between oral contraceptives and Enrylaze cannot be ruled out, patients of childbearing potential should use effective non-hormonal contraceptive methods while undergoing treatment (see section 4.6).

Sodium content
This medicinal product contains less than 1 mmol sodium (23 mg) per dose, that is to say, essentially ‘sodium-free’.

No interaction studies have been performed.

General
The possibility of interactions with medicinal products whose pharmacokinetics or pharmacodynamics are affected by asparaginase-induced changes in the liver function or plasma protein levels should be taken into account when administering asparaginase. Asparaginase may increase toxicity of other medicinal products through its effect on liver function.

Vincristine
Administration of asparaginase concurrently or immediately before vincristine may be associated with increased toxicity of vincristine. Asparaginase inhibits hepatic clearance of vincristine.

Methotrexate, cytarabine
Non-clinical data indicates that prior or concurrent administration of L-asparaginase attenuates the effect of methotrexate and cytarabine. Administration of L-asparaginase after methotrexate or cytarabine results in a synergistic effect. However, the clinical effect of sequence-dependent L-asparaginase administration on the efficacy of methotrexate and cytarabine is unknown.

Glucocorticoids
Administration of asparaginase with or immediately before glucocorticoids (e.g. prednisone) may change coagulation parameters, such as a decrease in fibrinogen and antithrombin III levels.

Women of childbearing potential/Contraception in males and females
Men and women should use contraception during treatment with Enrylaze containing chemotherapy.
Because the time period following treatment with asparaginase when it is safe to become pregnant or father a child is unknown, effective contraception should be used in men and women for at least 3 months after discontinuation. Since an indirect interaction between oral contraceptives and Enrylaze cannot be ruled out, patients of childbearing potential should use effective non-hormonal contraceptive methods while undergoing treatment (see section 4.4).

Pregnancy
There are no data on the use of recombinant crisantaspase in pregnant women. Based on studies with Erwinia chrysanthemi L-asparaginase in pregnant animals, recombinant crisantaspase can cause embryonic and foetal harm when administered to a pregnant woman (see section 5.3).

Women of childbearing potential should undergo pregnancy testing before initiation of Enrylaze.
Enrylaze should not be used during pregnancy, unless the clinical condition of the woman requires treatment and justifies the potential risk to the foetus. If the medicinal product is used during pregnancy, or if the patient becomes pregnant while receiving Enrylaze, the woman should be informed of the potential hazard to the foetus.

Breast-feeding
It is not known whether recombinant crisantaspase is excreted in human milk. Because of the potential for serious adverse reactions in breast-feeding infants/children, mothers should be advised not to breast-feed during Enrylaze therapy and for a period of two weeks after the last dose.

Fertility
No human data on the effect of recombinant crisantaspase on fertility are available. In a fertility and early embryonic development study in rats with Erwinia chrysanthemi crisantaspase, there were no effect on female or male fertility (margins of human exposure < 1) (see section 5.3).

Enrylaze has minor influence on the ability to drive and use machines. This influence is based on the adverse reactions that may occur during treatment (see section 4.8).

No case of Enrylaze overdose with clinical symptoms has been reported and there is no specific antidote. Treatment is symptomatic and supportive.

5.
PHARMACOLOGICAL PROPERTIES

Pharmacotherapeutic group: Other antineoplastic agents ATC code: L01XX02.

Mechanism of action
Asparaginase is an enzyme that catalyses the conversion of the amino acid L-asparagine into L-aspartic acid and ammonia. The pharmacological effect of Enrylaze is based on the killing of leukemic cells due to depletion of plasma asparagine. Leukemic cells with low expression of asparagine synthetase have a reduced ability to synthesize asparagine, and therefore is dependent on an exogenous source of asparagine for survival.

Clinical efficacy and safety
The efficacy and safety of Enrylaze was determined in the clinical trials, an open-label, two-part, multi-cohort, multi-centre, multi-agent chemotherapeutic trial that treated 228 adult and paediatric

patients with ALL or LBL who developed hypersensitivity to a long-acting E. coli-derived asparaginases. The median age of patients was 10 years (range, 1 to 25 years).

Prior long-acting E. coli-derived asparaginase treatments included pegaspargase for all patients apart from one who received other type of E. coli-derived asparaginase. In Study JZP458-201, 190 (83%) patients experienced a hypersensitivity (Grade ≥ 3) to a long-acting E. coli-derived asparaginases, 15 (7%) patients experienced silent inactivation, and 23 (10%) patients experienced an allergic reaction with inactivation. The number of courses of Enrylaze received ranged from 1 to 15.

Patients received 6 doses of Enrylaze, either intramuscularly at 25 mg/m2 or 37.5 mg/m2 three times a week (Monday/Wednesday/Friday), or 25 mg/m2 on Monday and Wednesday then 50 mg/m2 on Friday by intravenous infusion or an intramuscular injection as a replacement for each dose of E. coli derived asparaginase remaining on a patient’s treatment plan.

The determination of efficacy was based on demonstration of the achievement and maintenance of nadir serum asparaginase activity (NSAA) levels ≥ 0.1 U/mL. Serum trough asparaginase activity ≥ 0.1 U/mL has been demonstrated to correlate with asparagine depletion that predicts clinical efficacy (see section 5.2).

Observed NSAA levels during the clinical trials for indicated dosing schedules are presented in Table 2.

Table 2: Observed NSAA levels ≥ 0.1 U/mL during the clinical trials

Time Point
Intramuscularly 25 (MW)/
50 (F) mg/m2
Intravenously 25 (MW)/
50 (F) mg/m2
Last 48-hour
95.9%
[90.4%, 100.0%]
89.8%
[82.1%, 97.5%]
Last 72-hour
89.8%
[81.3%, 98.3%]
40.0%
[26.4%, 53.6%]
MW=Monday, Wednesday
MWF=Monday, Wednesday, Friday

The other recommended dosing schedules are based on interpolation from pharmacokinetic (PK) and response rates observed with the very similar investigated regimens.

Paediatric population
No clinically significant difference is expected in probability of achieving a therapeutic NSAA ≥ 0.1 U/mL based on age (1 month to 39 years) following the proposed Body surface area (BSA)-based dosing regimens.

The PK of Enrylaze was determined based on SAA. Patients received 6 doses of Enrylaze at various doses intramuscularly on Monday, Wednesday and Friday or 25 mg/m2 administered intramuscularly or intravenously on Monday and Wednesday and 50 mg/m2 on Friday as a replacement for each dose of a long-acting E. coli-derived asparaginase remaining on their original treatment plan. Recombinant crisantaspase maximum SAA (Cmax) and area under the SAA-time curve (AUC) increase approximately proportionally over a dose range from 12.5 to 50 mg/m2. The trough SAA at 48-hour (Ctrough,48) or 72-hour (Ctrough,72) post the last dose for recombinant crisantaspase are summarised in Table 3.

Table 3: Enrylaze pharmacokinetic parameters based on SAA
PK
Parametera
Mean (95% CI) after last dose
25/25/50 mg/m2
Monday, Wednesday, Friday

25/25/50 mg/m2
Monday, Wednesday,
Friday
Intramuscularly
Intravenously
Ctrough,48 (U/mL)
N =49