Summary of safety profile
The most common adverse reactions with mirvetuximab soravtansine were blurred vision (43%), nausea (41%), diarrhoea (39%), fatigue (35%), abdominal pain (30%), keratopathy (29%), dry eye (27%), constipation (26%), vomiting (23%), decreased appetite (22%), peripheral neuropathy (20%), headache (19%), asthenia (18%), AST increased (16%), and arthralgia (16%).
The most commonly reported serious adverse reactions were pneumonitis (4%), small intestinal obstruction (3%), intestinal obstruction (3%), pleural effusion (2%), abdominal pain (2%), dehydration (1%), constipation (1%), nausea (1%), ascites (1%) and thrombocytopenia (<1%).
Adverse reactions that most commonly led to dose reduction or dose delay were blurred vision (17%), keratopathy (10%), dry eye (5%), neutropenia (5%), keratitis (4%), cataract (3%), visual acuity reduced (3%), thrombocytopenia (3%), peripheral neuropathy (3%), and pneumonitis (3%).
Permanent discontinuation due to an adverse reaction occurred in 12% of patients who received mirvetuximab soravtansine, including most commonly, gastrointestinal disorders (4%), respiratory, thoracic, and mediastinal disorders (3%), blood and lymphatic system disorders (1%), nervous system disorders (1%), and eye disorders (1%).
Tabulated list of adverse reactions
The frequencies of adverse reactions are based on pooled data from 4 clinical studies which included 682 patients with epithelial ovarian, fallopian tube, or primary peritoneal cancer (collectively referenced as Epithelial Ovarian Cancer (EOC) treated with mirvetuximab soravtansine 6 mg/kg AIBW administered once every 3 weeks. The median duration of treatment with mirvetuximab soravtansine was 19.1 weeks (range: 3, 132 weeks).
The adverse reaction frequencies from clinical studies are based on all-cause adverse event frequencies, for which, after thorough assessment, a causal relationship between the medicinal product and the adverse event is at least a reasonable possibility.
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); very rare (<1/10 000). Within each frequency grouping, where relevant, adverse reactions are presented in order of decreasing seriousness.
Table 4: Tabulated list of all grade adverse reactions in patients treated with mirvetuximab soravtansine in clinical studies
| System Organ Class | Frequency category | Adverse reactions |
| Infections and infestations | Very common | Urinary tract infection |
| Blood and lymphatic system disorders | Very common | Anaemia, thrombocytopenia |
| Common | Neutropenia |
| Metabolism and nutrition disorders | Very common | Decreased appetite, hypomagnesaemia |
| Common | Hypokalaemia, dehydration |
| Psychiatric disorders | Common | Insomnia |
| Nervous system disorders | Very common | Peripheral neuropathy1, headache, |
| Common | Dysgeusia, dizziness |
| Eye disorders | Very common | Keratopathy2, cataract3, blurred vision event4, photophobia, eye pain, dry eye5 |
| Common | Ocular discomfort6 |
| Vascular disorders | Common | Hypertension |
| Respiratory, thoracic and mediastinal disorders | Very common | Pneumonitis7, dyspnoea, cough |
| Gastrointestinal disorders | Very common | Diarrhoea, abdominal pain8, constipation, abdominal distension, vomiting, nausea |
| Common | Ascites, gastro-oesophageal reflux disease, stomatitis, dyspepsia |
| Hepatobiliary disorders | Common | Hyperbilirubinaemia |
| System Organ Class | Frequency category | Adverse reactions |
| Skin and subcutaneous tissue disorders | Common | Pruritus |
| Musculoskeletal and connective tissue disorders | Very common | Arthralgia |
| Common | Myalgia, back pain, pain in extremity, muscle spasms |
| General disorders and administration site conditions | Very common | Fatigue |
| Common | Pyrexia |
| Investigations | Very common | Aspartate aminotransferase increased, alanine aminotransferase increased |
| Common | Blood alkaline phosphatase increased, gamma-glutamyl transferase increased, weight decreased |
| Injury, poisoning and procedural complication | Common | Infusion related reaction/hypersensitivity9 |
1 Peripheral neuropathy grouped term includes hypoaesthesia, neuropathy peripheral, neurotoxicity, paraesthesia, peripheral motor neuropathy, peripheral sensorimotor neuropathy, peripheral sensory neuropathy, and polyneuropathy (see section Description of selected adverse reactions).
2 Keratopathy group term includes corneal cyst, corneal deposits, corneal disorder, corneal epithelial microcysts, corneal epithelium defect, corneal erosion, corneal opacity, corneal pigmentation, keratitis, keratitis interstitial, keratopathy, limbal stem cell deficiency, and punctate keratitis (see section Description of selected adverse reactions).
3 Cataract grouped term includes cataract, cataract cortical, and cataract nuclear (see section Description of selected adverse reactions).
4 Blurred vision event grouped term includes accommodation disorder, diplopia, hypermetropia, presbyopia, refraction disorder, vision blurred, visual impairment, visual acuity reduced, and vitreous floaters (see section Description of selected adverse reactions).
5 Dry eye grouped term includes dry eye and lacrimation decreased (see section Description of selected adverse reactions).
6 Ocular discomfort grouped term includes eye irritation, eye pruritus, foreign body sensation in eye, and ocular discomfort (see section Description of selected adverse reactions).
7 Pneumonitis group term includes interstitial lung disease, organising pneumonia, pneumonitis, pulmonary fibrosis, and respiratory failure (see section Description of selected adverse reactions).
8 Abdominal pain grouped term includes abdominal discomfort, abdominal pain, abdominal pain lower, and abdominal pain upper.
9 Infusion related reaction/hypersensitivity grouped term includes SMQ Hypersensitivity narrow and flushing, erythema, erythema of eyelid.
Description of selected adverse reactions
Ocular disorders
Ocular adverse reactions (grouped terms) occurred in 59% of patients with EOC treated with mirvetuximab soravtansine. Eleven percent (11%) of patients experienced Grade 3 ocular adverse reactions and <1% experienced Grade 4 events. The most common ≥ Grade 3 ocular adverse reactions were blurred vision and keratopathy (both 5%, grouped terms) and cataract (4%).
The median time to onset for first ocular adverse reaction was 5.1 weeks (range: 0.1 to 68.6). Of the patients who experienced ocular events, 53% had complete resolution (Grade 0) and 38% had partial improvement (defined as a decrease in severity by one or more grades from the worst grade). At the last follow-up, 0.3% (2/682) patients had ≥ Grade 3 ocular adverse events (1 patient with Grade 3 decreased visual acuity and 1 patient with Grade 4 cataract).
Ocular adverse reactions led to dose delays in 24% of patients, and dose reductions in 15% of patients. Ocular adverse reactions led to permanent discontinuation of mirvetuximab soravtansine in 1% of patients.
Pneumonitis
Pneumonitis (grouped terms) occurred in 10% of patients with EOC treated with mirvetuximab soravtansine, including 0.9% (6/682) patients with Grade 3 events, and 0.2% (1/682) patient with a Grade 4 event. Two patients (0.3%) died due to respiratory failure. One patient (0.2%) died due to respiratory failure in the setting of Grade 1 pneumonitis and lung metastases confirmed at autopsy. One patient (0.2%) died due to respiratory failure of unknown aetiology without concurrent pneumonitis.
The median time to onset of pneumonitis was 18.1 weeks (range 1.6 to 97.0). Pneumonitis resulted in mirvetuximab soravtansine dose delays in 3%, dose reductions in 1%, and permanent discontinuation in 3% of patients.
Peripheral neuropathy
Peripheral neuropathy (grouped terms) occurred in 36% of patients with EOC treated with mirvetuximab soravtansine across clinical studies; 3% of patients experienced Grade 3 peripheral neuropathy.
The median time to onset of peripheral neuropathy was 5.9 weeks (range 0.1 to 126.7). Peripheral neuropathy resulted in mirvetuximab soravtansine dose delays in 2%, dose reductions in 4%, and led to permanent discontinuation in 0.7% of 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.