Binimetinib

Binimetinib is primarily metabolised through UGT1A1 mediated glucuronidation. The extent of drug interactions mediated by UGT1A1 is unlikely to be clinically relevant; however, as this has not been evaluated in a formal clinical study, UGT1A1 inducers (such as rifampicin and phenobarbital) and inhibitors (such as indinavir, atazanavir, sorafenib) should be co-administered with caution.

While encorafenib is a relatively potent reversible inhibitor of UGT1A1, no differences in binimetinib exposure have been observed clinically when binimetinib is co-administered with encorafenib.

Binimetinib is a weak inhibitor of OAT3, and caution should be taken when it is used with sensitive substrates (such as pravastatin or ciprofloxacin).

Inducers of CYP1A2 enzymes (such as carbamazepine and rifampicin) and inducers of Pgp transport (such as Saint John’s wort or phenytoin) may decrease binimetinib exposure, which could result in a decrease of efficacy.

Binimetinib is a potential inducer of CYP1A2, and caution should be taken when it is used with sensitive substrates (such as duloxetine or theophylline).

Liver metabolism mainly via glucuronidation is the primary route of elimination of binimetinib. As encorafenib is not recommended in patients with moderate (Child Pugh B) and severe hepatic impairment (Child Pugh C), administration of binimetinib is not recommended in these patients.

Binimetinib is not recommended in patients with a history of RVO. The safety of binimetinib has not been established in patients with predisposing factors for RVO including uncontrolled glaucoma, ocular hypertension, uncontrolled diabetes mellitus or a history of hyperviscosity or hypercoagulability syndromes. Therefore, binimetinib should be used with caution in these patients.

The safety of binimetinib in combination with encorafenib has not been established in patients with a baseline LVEF that is either below 50% or below the institutional LLN. Therefore, in these patients, binimetinib should be used with caution and for any symptomatic left ventricular dysfunction, Grade 3-4 LVEF, or absolute decrease of LVEF from baseline of ≥10%, binimetinib should be discontinued and LVEF should be evaluated every 2 weeks until recovery.

Binimetinib should be used with caution in patients who are at risk for, or who have a history of VTE.

There are no data from the use of binimetinb in pregnant women. Studies in animals have shown reproductive toxicity. Binimetinib is not recommended during pregnancy and in women of childbearing potential not using contraception. If binimetinib is used during pregnancy, or if the patient becomes pregnant while taking binimetinib, the patient should be informed of the potential hazard to the foetus.

It is unknown whether binimetinib or its metabolite are excreted in human milk. A risk to the breastfed newborns/infants cannot be excluded. A decision must be made whether to discontinue breast-feeding or to discontinue binimetinib therapy taking into account the benefit of breast-feeding for the child and the benefit of therapy for the mother.

Women of childbearing potential/Contraception in females

Women of childbearing potential must use effective contraception during treatment with binimetinib and for at least 1 month following the last dose.

Fertility

There are no data on the effect on fertility in humans for binimetinib.

Binimetinib has minor influence on the ability to drive or use machines. Visual disturbances have been reported in patients treated with binimetinib during clinical studies. Patients should be advised not to drive or use machines if they experience visual disturbances or any other adverse reaction that may affect their ability to drive and use machines.

Summary of safety profile

The safety of binimetinib (45 mg orally twice daily) in combination with encorafenib (450 mg orally once daily) has been evaluated in the integrated safety population (ISP) of 372 patients including patients with BRAF V600 mutant unresectable or metastatic melanoma and BRAF V600E mutant advanced NSCLC (hereafter referred to as Combo 450 ISP). In Combo 450 ISP, 274 patients received the combination for the treatment of BRAF V600 mutant unresectable or metastatic melanoma (in two Phase II studies (CMEK162X2110 and CLGX818X2109) and one Phase III study (CMEK162B2301, Part 1), and 98 received the combination for the treatment of BRAF V600E mutant advanced NSCLC (in one non-randomized Phase II study (ARRAY-818-202)).

The most common adverse reactions (>25%) occurring in patients treated with binimetinib administered with encorafenib were fatigue, nausea, diarrhoea, vomiting, abdominal pain, myopathy/muscular disorders and arthralgia.

The safety of encorafenib (300 mg orally once daily) in combination with binimetinib (45 mg orally twice daily) was evaluated in 257 patients with BRAF V600 mutant unresectable or metastatic melanoma (hereafter referred to as the Combo 300 population), based on the Phase III study (CMEK162B2301, Part 2). The most common adverse reactions (>25%) occurring in patients treated with encorafenib 300 mg administered with binimetinib were fatigue, nausea and diarrhoea.

Tabulated list of adverse reactions

Adverse reactions are listed below by MedDRA body system organ class and the following frequency convention: 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 the available data). Within each frequency grouping, adverse reactions are presented in order of decreasing seriousness.

Adverse reactions occurring in patients receiving binimetinib in combination with encorafenib at the recommended dose (n=372):

^* composite terms which included more than one preferred term
^a includes keratoacanthoma, squamous cell carcinoma and squamous cell carcinoma of skin
^b includes, but not limited to, angioedema, drug hypersensitivity, hypersensitivity, hypersensitivity vasculitis, and urticaria
^c includes facial nerve disorder, facial paralysis, facial paresis, Bell’s palsy
^d includes left ventricular dysfunction, ejection fraction decreased, cardiac failure and ejection fraction abnormal
^e includes haemorrhage at various sites including, but not limited to, cerebral haemorrhage, intracranial haemorrhage, vaginal haemorrhage, heavy menstrual bleeding, intermenstrual bleeding, haematochezia, haemoptysis, haemothorax, gastrointestinal haemorrhage and haematuria
^f includes, but not limited to, pulmonary embolism, deep vein thrombosis, embolism, thrombophlebitis, thrombophlebitis superficial, thrombosis, phlebitis, superior vena cava syndrome, mesenteric vein thrombosis and vena cava thrombosis
^g includes colitis, colitis ulcerative, enterocolitis and proctitis
^h includes myalgia, muscular weakness, muscle spasm, muscle injury, myopathy, myositis
ⁱ includes, but not limited to, fluid retention, peripheral oedema, localised oedema, generalised oedema and swelling

When encorafenib was used at a dose of 300 mg once daily in combination with binimetinib 45 mg twice daily (Combo 300) in study CMEK162B2301-Part 2, the frequency category was lower compared to the pooled Combo 450 population for the following adverse reactions: anaemia, peripheral neuropathy, haemorrhage, hypertension, pruritus (common) and colitis, increased amylase and increased lipase (uncommon).

Description of selected adverse reactions

Cutaneous malignancies

CuSCC was reported when binimetinib was used in combination with encorafenib.

Ocular events

In the Combo 450 ISP, RPED was reported in 22.3% (83/372) of patients. RPED was Grade 1 (asymptomatic) in 15.6% (58/372) of patients, Grade 2 in 5.1% (19/372) of patients and Grade 3 in 1.6% (6/372) of patients. Most events were reported as retinopathy, retinal detachment, subretinal fluid, macular oedema, and central serous chorioretinopathy and led to dose interruptions or dose modifications in 3.8% (14/372) of patients. The median time to onset of the first event of RPED (all grades) was 1.4 month (range 0.0 to 17.5 months). Visual impairment, including vision blurred and reduced visual acuity, occurred in 23.1% (86/372) of patients. Visual impairment was generally reversible.

Uveitis was also reported when binimetinib was used in combination with encorafenib.

In Study CMEK162B2301-Part 2, in the Combo 300 arm, RPED was observed in 12.5% (32/257) of patients with 0.4% (1/257) Grade 4 event.

Left ventricular dysfunction

In the Combo 450 ISP, LVD was reported in 9.4% (35/372) of patients. Grade 3 events occurred in 1.3% (5/372) of patients. LVD led to treatment discontinuation in 0.8% (3/372) of patients and led to dose interruptions or dose reductions in 6.2% (23/372) of patients.

The median time to first occurrence of LVD (any grade) was 5.2 months (range 0.0 to 25.7 months) in patients who developed an LVEF below 50%. The mean LVEF value dropped by 5.3% in the Combo 450 ISP, from a mean of 63.3% at baseline to 58.0%. LVD was generally reversible following dose reduction or dose interruption.

Haemorrhage

Haemorrhagic events were observed in 16.7% (62/372) of patients in the Combo 450 ISP. Most events were Grade 1 or 2:13.2% (49/372) and 3.5% (13/372) were Grade≥ 3. Few patients requiring dose interruptions or dose reductions (2.4% or 9/372). Haemorrhagic events led to discontinuation of treatment in 0.8% (3/372) of patients. The most frequent haemorrhagic events were haematuria in 2.7% (10/372) of patients, haematochezia in 2.7% (10/372) and rectal haemorrhage in 2.2% (8/372) of patients. Fatal gastric ulcer haemorrhage with multiple organ failure as a concurrent cause of death, occurred in one patient. Cerebral haemorrhage/intracranial haemorrhage occurred in 1.3% (5/372) of patients with fatal outcome in 4 patients. All events occurred in the setting of new or progressive brain metastases.

In Study CMEK162B2301-Part 2, in the Combo 300 arm, haemorrhagic events were observed in 6.6% (17/257) of patients and were Grade 3-4 in 1.6% (4/257) of patients.

Hypertension

New onset elevated blood pressure or worsening of pre-existing hypertension were reported in 11.0% (41/372) of patients treated with the Combo 450 ISP. Hypertension events were reported as Grade 3 in 5.1% (19/372) of patients, including hypertensive crisis (0.3% (1/372). Hypertension led to dose interruption or adjustment in 2.2% (8/372) of patients. Hypertensive adverse reactions required additional therapy in 7.5% (28/372) of patients.

Venous thromboembolism

In the Combo 450 ISP, VTE occurred in 4.8% (18/372) of patients, including 1.9% (7/372) of patients who developed pulmonary embolism. VTE was reported as Grade 1 or 2 in 4.0% (15/372) of patients and Grade 3 or 4 in 0.8% (3/372) of patients. VTE led to dose interruptions or dose modifications in 1.1% (4/372) patients and to additional therapy in 4.6% (17/372) of patients.

Pancreatitis

Pancreatitis was reported when binimetinib was used in combination with encorafenib.

Dermatologic reactions

Dermatologic reactions may occur when binimetinib is used in combination with encorafenib.

Rash

In the Combo 450 ISP, rash occurred in 20.4% (76/372) of patients. Most events were mild, with Grade 3 or 4 events reported in 1.1% (4/372) of patients. Rash led to treatment discontinuation in 0.8% (3/372) of patients and to dose interruption or dose modification in 2.4% (9/372) of patients.

Dermatitis acneiform

In the Combo 450 ISP, dermatitis acneiform occurred in 4.0% (15/372) of patients. Dermatitis acneiform was reported as Grade 1 or 2 in 3.8% (14/372) of patients and Grade 3 in 0.3% (1/372) of patients. No event led to treatment discontinuation. Dose modification was reported in 0.5% (2/372) of patients.

Palmar-plantar erythrodysaesthesia syndrome

PPES can occur when binimetinib is used in combination with encorafenib.

Photosensitivity

In the Combo 450 ISP, photosensitivity was observed in 4.3% (16/372) of patients. Most events were Grade 1-2, with Grade 3 reported in 0.3% (1/372) of patients and no event led to discontinuation. Dose interruption or dose modification was reported in 0.3% (1/372) of patients.

Facial paresis

Facial paresis was reported when binimetinib was used in combination with encorafenib.

CK elevation/rhabdomyolysis

In the Combo 450 ISP, mostly mild asymptomatic blood CK elevation was reported in 23.9% (89/372) of patients. The incidence of Grade 3 or 4 adverse reactions was 5.1% (19/372). The median time to onset of the first event was 2.8 months (range: 0.5 to 26 months).

Rhabdomyolysis was reported in 0.3% (1/372) of patients treated with encorafenib in combination with binimetinib. In this patient, rhabdomyolysis was observed with concomitant symptomatic Grade 4 CK elevation.

Renal dysfunction

Blood creatinine elevation and renal failure occurred when binimetinib was used in combination with encorafenib.

Liver laboratory abnormalities

The incidences of liver laboratory abnormalities reported in the Combo 450 ISP are listed below:

• Increased transaminases: 16.4% (61/372) overall – 6.5% (24/372) Grade 3
• Increased GGT: 11.3% (42/372) overall – 6.7% (25/372) Grade 3-4 In Study CMEK162B2301-Part 2, in the Combo 300 arm, the incidences of liver laboratory abnormalities are listed below:
• Increased transaminases: 13.2% (34/257) overall – 5.4% (14/257) Grade 3-4
• Increased GGT: 14.0% (36/257) overall – 4.7% (12/257) Grade 3-4

Gastrointestinal disorders

In the Combo 450 ISP, diarrhoea was observed in 41.7% (155/372) of patients and was Grade 3 or 4 in 3.8% (14/372) of patients. Diarrhoea led to dose discontinuation in 0.8% of patients and to dose interruption or dose modification in 8.1% of patients. Constipation occurred in 24.7% (92/372) of patients and was Grade 1 or 2. Abdominal pain was reported in 28.5% (106/372) of patients and was Grade 3 in 2.2% (8/372) patients. Nausea occurred in 46.0% (171/372) with Grade 3 observed in 3.0% (11/372) of patients. Vomiting occurred in 31.2% (116/372) of patients with Grade 3 reported in 1.9% (7/372) of patients.

In Study CMEK162B2301-Part 2, in the Combo 300 arm, nausea was observed in 27.2% (70/257) of patients and was Grade 3 in 1.6% (4/257) of patients. Vomiting occurred in 15.2% (39/257) of patients with Grade 3 reported in 0.4% (1/257) of patients. Diarrhoea occurred in 28.4% (73/257) of patients with Grade 3 reported in 1.6% (4/257) of patients.

Gastrointestinal disorders were typically managed with standard therapy.

Anaemia

In the Combo 450 ISP, anaemia was reported in 23.1% (86/372) of patients; 7.0% (26/372) of patients had Grade 3 or 4. No patients discontinued treatment due to anaemia, 3.2% (12/372) required dose interruption or dose modification.

In Study CMEK162B2301-Part 2, in the Combo 300 arm, anaemia was observed in 9.7% (25/257) of patients with Grade 3-4 reported in 2.7% (7/257) patients.

Headache

In the Combo 450 ISP, headache occurred in 18.8% (70/372) of patients including Grade 3 in 1.1% (4/372) of patients.

In Study CMEK162B2301-Part 2, in the Combo 300 arm, headache was reported in 12.1% (31/257) of patients and was Grade 3 in 0.4% (1/257) of patients.

Fatigue

In the Combo 450 ISP, fatigue occurred in 48.1% (179/372) of patients including Grade 3 or 4 in 4.3% (16/372) of patients. In Study CMEK162B2301-Part 2, in the Combo 300 arm, fatigue was observed in 33.5% (86/257) of patients with 1.6% (4/257) Grade 3-4 events.

Special populations

Elderly

In patients treated with Combo 450 ISP (n=372), 230 patients (61.8%) were <65 years old, 107 patients (28.8%) were 65-74 years old and 35 patients (9.4%) were aged >75. No overall differences in safety or efficacy were observed between elderly patients (≥65) and younger patients except diarrhoea and pruritus that were more frequently reported in elderly patients. In the age subgroup of patients aged ≥75 years, Grade ≥3 adverse reactions (62.9% vs 47.5%), adverse reactions (all grades) requiring dose modification of any study drug (60.0% vs 48.1%) or leading to treatment discontinuation (25.7% vs 7.4%) were more frequently reported than in patients <75 years. The most common adverse reactions reported with a higher incidence in patients aged ≥75 years compared to patients aged <75 years included fatigue, nausea, diarrhoea, vomiting and anaemia.