Summary of the safety profile
The safety of selumetinib monotherapy has been evaluated in a pooled safety population of 126 paediatric patients (20-30 mg/m2 twice daily, capsules) from 4 studies with NF1 and inoperable PN [(NF1-PN Paediatric Pool, which includes safety data from SPRINT Phase I (N=24), SPRINT Phase II, Stratum 1 (N=50), China Phase I study; paediatric cohort (N=16), Japan Phase I study (N=12), and Phase I Food effect study (Study 15, N=24)].
In addition, the safety of selumetinib for the granule formulation was evaluated in 36 paediatric patients (dose equivalent to 25 mg/m2 twice daily, granules) with NF1 and symptomatic inoperable PN from the Phase I/II SPRINKLE study.
The safety of selumetinib monotherapy in adult patients has been evaluated in 137 adult patients with NF1 and inoperable PN (25 mg/m2 twice daily, capsules) from Phase III KOMET study.
The median total duration of selumetinib treatment in NF1-PN Paediatric Pool was 27 months (range: < 1– 97 months), 57% of patients were exposed to selumetinib treatment for > 24 months and 40% for > 36 months. The median total duration of selumetinib treatment in NF1-PN adult patients was about 12 months (range: < 1 – 32 months). Of these patients 50.4% of patients were exposed to selumetinib treatment for < 12 months and remaining 49.6% patients were exposed to selumetinib for > 12 months.
In the NF1-PN Paediatric pool, the most common adverse reactions of any grade (incidence ≥ 40%) were vomiting (62%), acneiform rashes (60%), diarrhoea (56%), blood creatine phosphokinase increased (54%), nausea (52%), paronychia (50%), and dry skin and pyrexia (44% each). Adverse events leading to dose interruptions and reductions were reported in 61.9% and 27.8% of patients, respectively. A total of 47.6% patients had ADRs leading to dose modification of selumetinib (either dose interruptions or reductions). The ADRs leading to dose modification (incidence ≥ 5%) of selumetinib were vomiting (19.8%), paronychia (15.9%), nausea (11.1%), diarrhea (8.7%), pyrexia (6.3%), and rashes (acneiform and non-acneiform; 5.6% each). Any ADRs leading to treatment discontinuation were reported in 4.8% patients.
In the SPRINKLE study, at the time of first data cut-off (DCO1), the median total duration of selumetinib treatment was 11 months (range: < 3 – < 26 months). Thirty-six paediatric patients were treated with selumetinib granules equivalent to 25 mg/m2 twice daily. The most common adverse reactions of any grade (incidence ≥ 40%) were pyrexia and dry skin (47% patients each); and paronychia (44%). Adverse events leading to dose interruptions were reported in 30.6% of patients, while no patients had AEs leading to dose reductions. A total 22.2% patients had ADRs leading to dose modification (either dose interruptions or reductions). The ADRs leading to dose modification (incidence ≥ 5%) were vomiting and pyrexia (11.1% patients each), and diarrhea (5.6%). No patient had ADRs that led to treatment discontinuation.
The observed safety profile of selumetinib granules in the SPRINKLE study was comparable with pooled safety data in paediatric patients treated with selumetinib capsules (NF1-PN Paediatric Pool).
In the NF1-PN adult patients, the most common adverse reactions of any grade (incidence ≥ 20%) were acneiform rashes (55%), blood creatine phosphokinase increased (37%), diarrhoea (30%), non-acneiform rashes (27%) and vomiting (20%). A total of 25.5% patients had adverse reactions leading to dose modification of selumetinib (either dose interruptions or reductions). The adverse drug reaction (ADR) leading to dose modification (incidence ≥ 5%) of selumetinib was blood creatine phosphokinase increased (5.8%). The adverse reactions leading to treatment discontinuation were reported in 1.5% patients.
The safety profile was also substantiated by a pool of safety data from 7 studies in adult patients with multiple tumour types (N=347) who received 75 to 100 mg of selumetinib twice daily.
Tabulated list of adverse reactions
Table 5 presents the adverse reactions identified in the paediatric and adult population with NF1 who have inoperable PN and also in adult patients with multiple tumour types (see footnote to Table 5). The frequency is determined from the paediatric pool (N = 126) and adult patients (N = 137) as defined above. Adverse drug reactions (ADRs) are organised by MedDRA system organ class (SOC). Within each SOC, preferred terms are arranged by decreasing frequency and then by decreasing seriousness. Frequencies of occurrence of adverse reactions 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); very rare (< 1/10,000) and not known (cannot be estimated from available data), including isolated reports.
Table 5. Adverse drug reactions reported in the selumetinib NF1-PN studies and in other identified clinical trials in adult patients with multiple tumour types
| MedDRA SOC and MedDRA term | Paediatric Pool a (N = 126) | KOMET Study b (N = 137) |
| Overall Frequency (All CTCAE Grades) c | Frequency of CTCAE Grade 3 and above d | Overall Frequency (All CTCAE Grades) c | Frequency of CTCAE Grade 3 and above e |
| Eye disorders |
| Vision blurred ^ | Common (9%) | - | Common (4%) | - |
| Retinal pigment epithelial detachment (RPED)/ Central serous retinopathy (CSR) * †† | - | - | Uncommon (0.6%) | - |
| Retinal vein occlusion (RVO) * †† | - | - | Uncommon (0.3%) | - |
| Respiratory, thoracic and mediastinal disorders |
| Dyspnoea * | Common (6%) | - | Common (3%) | Common (1%) |
| Gastrointestinal disorders |
| Vomiting ^ | Very common (62%) | Common (7%) | Very common (20%) | - |
| Diarrhoea ^ | Very common (56%) | Very common (10%) | Very common (30%) | - |
| Nausea ^ | Very common (52%) | Common (2%) | Very common (17%) | - |
| Stomatitis ^* | Very common (40%) | Common (1%) | Very common (14%) | Common (1%) |
| Constipation | - | - | Very common (10%) | - |
| Dry mouth | Common (4%) | - | Common (6%) | - |
| Skin and subcutaneous tissue disorders |
| Rashes (acneiform) ^* | Very common (60%) | Common (2%) | Very common (55%) | Common (2%) |
| Paronychia ^ | Very common (50%) | Very common (10%) | Very common (17%) | Common (3%) |
| Dry skin | Very common (44%) | Common (1%) | Very common (13%) | - |
| Rashes (non-acneiform) ^* | Very common (39%) | Common (2%) | Very common (27%) | Common (1%) |
| Hair changes ^* | Very common (29%) | - | Very common (18%) | - |
| General disorders |
| Pyrexia | Very common (44%) | Common (5%) | Common (5%) | Common (1%) |
| Asthenic events * | Very common (37%) | - | Very common (15%) | - |
| Peripheral oedema * | Very common (18%) | - | Very common (16%) | - |
| Facial oedema * | Common (8%) | - | Common (4%) | - |
| Investigations f |
| Blood CPK increased ^ | Very common (54%) | Common (6%) | Very common (37%) | Common (7%) |
| AST increased | Very common (37%) | Common (2%) | Very common (12%) | Common (1%) |
| Haemoglobin decreased * | Very common (35%) | Common (2%) | Very common (11%) | Common (2%) |
| Blood albumin decreased * | Very common (35%) | - | Common (2%) | - |
| ALT increased | Very common (29%) | Common (2%) | Very common (11%) | Common (1%) |
| Ejection fraction decreased ^ | Very common (21%) | Common (1%) | Common (7%) | Common (1%) |
| Blood creatinine increased | Very common (19%) | Common (1%) | Common (2%) | - |
| Increased blood pressure * | Very common (11%) | - | Common (4%) | Common (2%) |
a NF1-PN Paediatric Pool data (N = 126) is pooled from SPRINT Phase I (N = 24), SPRINT Phase II, Stratum 1 (N = 50), China Phase I study; paediatric cohort (N=16), Japan Phase I Study (N=12), and Phase I Food effect (N=24) studies. Frequency percentage numbers are rounded to the nearest full number.
b NF1-PN adult patients data is from KOMET study (N = 137). Frequency percentage numbers are rounded to the nearest full number.
c Per National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE), all studies used CTCAE v5.0, except for SPRINT paediatric study which used CTCAE v4.03.
d All events were CTCAE grade 3, except for two CTCAE grade 4 event of blood CPK increased and one CTCAE grade 4 event of blood creatinine increased. There were no deaths.
e All events were CTCAE grade 3, except for one CTCAE grade 4 event of pyrexia and four CTCAE grade 4 events of blood CPK increased. There were no deaths.
f In the SPRINT study, all lab abnormalities were reported as AEs. In other studies included in the NF1-PN paediatric and adult patients, lab abnormalities were only reported as AEs when they met SAE criteria, resulted in discontinuation, or were clinically relevant as judged by the investigator.
CPK = creatine phosphokinase; AST = aspartate aminotransferase; ALT = alanine aminotransferase
^ See Description of selected adverse reactions
†† Identified ADRs from other clinical trial experience in adult patients (N = 347), with multiple tumour types, receiving treatment with selumetinib (75 mg twice daily). These ADRs have not been reported in paediatric or adult population with NF1 who have inoperable PN.
* ADRs based on grouping of individual Preferred Terms (PT):
Asthenic events: fatigue, asthenia
Blood albumin decreased: hypoalbuminaemia, blood albumin decreased
CSR/RPED: detachment of macular retinal pigment epithelium, chorioretinopathy
Dyspnoea: dyspnoea exertional, dyspnoea, dyspnoea at rest
Facial oedema: periorbital oedema, face oedema, lip swelling, eyelid oedema, swelling face
Haemoglobin decreased: anaemia, haemoglobin decreased
Hair changes: alopecia, hair colour change
Increased blood pressure: blood pressure increased, hypertension
Peripheral oedema: oedema peripheral, oedema, localised oedema, peripheral swelling
Rashes (acneiform): dermatitis acneiform, acne, folliculitis
Rashes (non-acneiform): rash pruritic, rash maculo-papular, rash papular, rash, rash erythematous, rash macular
RVO: retinal vascular disorder, retinal vein occlusion, retinal vein thrombosis
Stomatitis: stomatitis, mouth ulceration, aphthous ulcer, gingival swelling
Description of selected adverse reactions
Left ventricular ejection fraction (LVEF) reduction
In the NF1-PN Paediatric Pool (N=126), LVEF reduction (PT: ejection fraction decreased) was reported in 26 (21%) patients; among them, in 25 (19.8%) patients, the reported ADRs were CTCAE grade 2, and in 1 (0.8%) patient, the ADR reported was CTCAE grade 3. In 4 (3.2%) patients, LVEF decrease led to dose reduction and in 2 (1.6%) patients, LVEF decrease led to dose interruption. At the time of analysis, of the 26 patients, 20 patients were recovered. The median time to first occurrence of LVEF reduction was 283 days (median duration 110.5 days).
In the NF1-PN adult patients (N = 137), LVEF reduction (PT: ejection fraction decreased) was reported in 10 (7%) patients; among them, in 1 (0.7%) patient, the reported ADR was CTCAE grade 3. In 2 (1.5%) patients, LVEF decrease led to dose interruption. At the time of analysis, 7 of the 10 patients had recovered. The median time to first occurrence of LVEF reduction was 342 days (approximately 11 months) [median duration 112.5 days (approximately 4 months)].
Patients with LVEF lower than the institutional LLN at baseline were not included in the pivotal studies. In addition, a small number of serious cases of LVEF reduction associated with selumetinib have been reported in paediatric patients who participated in an expanded access program. For clinical management of LVEF reduction (see sections 4.2 and 4.4).
Ocular toxicity
In the NF1-PN Paediatric Pool (N=126), CTCAE grade 1 and 2 events of blurred vision were reported in 11 (9%) patients. Two patients (1.6%) required dose interruption. At the time of analysis, of the 11 patients, 10 patients were recovered.
In the NF1-PN adult patients (N = 137), CTCAE grade 1 event of blurred vision was reported in 5 (4%) patients. One patient (0.7%) required dose interruption. All events were managed without dose reduction and at the time of analysis, all 5 patients had recovered.
For clinical management of new visual disturbances (see sections 4.2 and 4.4).
In addition, a single event of RPED was reported in a paediatric patient receiving selumetinib monotherapy (25 mg/m2 twice daily) for pilocytic astrocytoma involving the optic pathway in an externally sponsored paediatric study (see sections 4.2 and 4.4).
Paronychia
In the NF1-PN Paediatric Pool (N=126), paronychia was reported in 63 (50%) patients. The median time to first onset of maximum grade paronychia adverse event was 375 days (approximately 12 months) and the median duration of events was 55 days (approximately 2 months). The majority (51 patients, 40.5% the NF1-PN Paediatric Pool) had a maximum CTCAE grade of 1 or 2. Grade ≥ 3 events occurred in 12 (10%) patients. Eighteen patients (14.3%) required dose interruption for adverse event of paronychia, and 9 patients (7.1%) had an AE of paronychia that led to dose reduction. In one patient (0.8%) the event led to treatment discontinuation.
In the NF1-PN adult patients (N = 137), paronychia was reported in 23 (17%) patients. The median time to first onset of maximum grade paronychia was 390 days (approximately 13 months) and the median duration of the maximum grade event was 63 days (approximately 2 months). Nineteen (13.9%) patients had a maximum CTCAE grade of 1 or 2. Grade 3 events occurred in 4 (3%) patients. One patient (0.7%) required dose interruption for adverse event of paronychia, and 3 patients (2.2%) had an event of paronychia that led to dose reduction. Paronychia did not lead to dose discontinuation in any of the patients. At the time of analysis, 11 of the 23 patients had recovered.
Blood creatine phosphokinase (CPK) increase
ADRs of blood CPK elevation occurred in 68 (54%) patients in the NF1-PN Paediatric Pool (N=126). The median time to first onset of the maximum CTCAE grade CPK increase was 112 days (approximately 4 months) and the median duration of the maximum CTCAE grade event was 126 days (approximately 4 months). The majority (61 cases, 48.4% of the NF1-PN Paediatric Pool) had maximum CTCAE grade event that was grade 1 or 2. A maximum CTCAE grade 3 events occurred in 5 (4%) patients, and CTCAE grade 4 event occurred in 2 (1.6%) patients. Five patients had an AE of blood CPK increase that led to treatment interruptions and required dose reduction.
In the NF1-PN adult patients (N = 137), ADRs of blood CPK increase occurred in 51 (37%) patients. The median time to first onset of the maximum CTCAE grade blood CPK increase was 167 days (approximately 6 months), and the median duration of maximum grade event was 122 days (approximately 4 months). Forty-two patients (30.7%) had maximum CTCAE grade of 1 or 2. A maximum CTCAE grade 3 events occurred in 5 (3.6%) patients, and CTCAE grade 4 events occurred in 4 (2.9%) patients. Six patients had an event of blood CPK increase that led to dose interruptions and dose reduction was required in 3 patients. At the time of analysis, 21 of the 51 patients had recovered.
Gastrointestinal toxicities
In the NF1-PN Paediatric Pool (N=126), vomiting (78 patients, 62%), diarrhoea (71 patients, 56%), nausea (66 patients, 52%), and stomatitis (50 patients, 40%) were the most commonly reported gastrointestinal (GI) events. The majority of these cases were CTCAE grade 1 or 2. CTCAE grade ≥ 3 events were reported for diarrhoea (10%), vomiting (7%), nausea (2%) and stomatitis (1%). Dose modification was required in 25 (19.8%) patients with vomiting, 14 (11.1%) with nausea, 11 (8.7%) with diarrhoea, and 6 (4.8%) with stomatitis. One patient each reported an event of diarrhoea, nausea and stomatitis led to treatment discontinuation. Dose reduction had occurred in one patient with AE of diarrhoea and in 2 patients with AE of stomatitis. No CTCAE grade ≥ 4 events were reported.
In the NF1-PN adult patients (N = 137), diarrhoea (41 patients, 30%), vomiting (27 patients, 20%), nausea (23 patients, 17%), stomatitis (19 patients, 14%), and constipation (13 patients, 10%) were the most reported gastrointestinal (GI) events. Most of these events were CTCAE grade 1 or 2. In 1 patient (0.7%), CTCAE grade 3 event was reported for stomatitis. Dose interruption was required in 2 patients (1.5%) each with nausea and vomiting, and in 1 patient (0.7%) each with diarrhoea and stomatitis. Dose reduction occurred in 1 patient (0.7%) each with an ADR of nausea and stomatitis. One patient reported an event of nausea that led to treatment discontinuation.
Skin toxicities
In the NF1-PN Paediatric Pool (N=126), acneiform rashes were observed in 76 (60%) patients [median time to onset 29 days; median duration of 176 days (approximately 6 months) for the maximum CTCAE grade event]. The majority (73 patients, 58% of the NF1-PN Paediatric Pool) of these reported ADRs with maximum CTCAE were grade 1 or 2. In 4 patients (3.2%), acneiform rashes led to dose interruption and 3 patients (2.4%) acneiform rashes led to dose reduction. CTCAE grade 3 events were reported in 3 (2.4%) patients. Other (non-acneiform) rashes were observed in 49 (39%) patients in the NF1-PN Paediatric Pool and were predominantly (46 patients, 36.5% of the NF1-PN Paediatric Pool) CTCAE grade 1 or 2.
In the NF1-PN adult patients (N = 137), acneiform rashes were observed in 75 (55%) patients [median time to onset 19 days; median duration of 124 days (approximately 4 months) for the maximum CTCAE grade event]. Seventy-two (53%) patients reported ADRs with maximum CTCAE grade 1 or 2. CTCAE grade 3 events were reported in 3 (2.2%) patients. In 3 patients (2.2%) acneiform rashes led to dose interruption, and in 2 patients (1.5%) each acneiform rashes led to dose reduction and dose discontinuation. Rashes (non-acneiform) were observed in 37 (27%) patients and were predominantly (36 patients, 26.3%) CTCAE grade 1 or 2.
Hair changes
In the NF1-PN Paediatric Pool (N=126), 37 (29%) patients experienced hair changes adverse event (reported as [PT: hair colour changes] in 21 patients (16.7%) and hair thinning [PT: alopecia] in 30 patients (23.8%)). All cases were CTCAE grade 1 (33 patients, 26.2%) or 2 (4 patients, 3.2%) and dose interruption was reported in 1 (0.8%) patient.
In the NF1-PN adult patients (N = 137), 24 (18%) patients experienced hair changes adverse event [reported as (PT: hair colour changes) in 6 (4.4%) patients and hair thinning (PT: alopecia) in 20 (14.6%) patients]. All cases were CTCAE grade 1 or 2. Dose interruption was reported in 1 (0.7%) patient and dose reduction in 2 (1.5%) patients.
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 Yellow Card Scheme Website: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.