Summary of the safety profile
Two parallel, 24-week, randomised, double-blind, placebo-controlled clinical studies were conducted with tobramycin in 520 cystic fibrosis patients ranging in age from 6 to 63 years.
The most commonly (≥ 10%) reported adverse events in the placebo-controlled studies with tobramycin were cough, pharyngitis, productive cough, asthenia, rhinitis, dyspnoea, pyrexia, lung disorder, headache, chest pain, sputum discoloured, haemoptysis, anorexia, pulmonary function test decreased, asthma, vomiting, abdominal pain, dysphonia, nausea, and weight loss.
Most events were reported at similar or higher frequencies in patients receiving placebo. Dysphonia and tinnitus were the only undesirable effects reported in significantly more patients treated with tobramycin; (12.8% tobramycin vs. 6.5% placebo) and (3.1% tobramycin vs. 0% placebo) respectively. These episodes of tinnitus were transient and resolved without discontinuation of tobramycin therapy, and were not associated with permanent loss of hearing on audiogram testing. The risk of tinnitus did not increase with repeated cycles of exposure to tobramycin (see section 4.4 Ototoxicity).
Tabulated summary of adverse reactions
In the 24-week placebo-controlled studies and their open-label extensions on active treatment, a total of 313, 264 and 120 patients completed treatment with tobramycin for 48, 72 and 96 weeks respectively.
Table 1 provides the incidence of treatment-emergent adverse drug reactions, according to the following criteria: reported with an incidence of ≥ 2% for patients receiving tobramycin, occurring at a higher rate in tobramycin arm, and assessed as drug-related in ≥ 1% of patients.
Adverse drug reactions from clinical trials are listed according to system organ classes in MedDRA. Within each system organ class, the adverse drug reactions are ranked by frequency, with the most frequent reactions first. Within each frequency grouping, adverse drug reactions are presented in order of decreasing seriousness. In addition, the corresponding frequency category using the following convention (CIOMS III) is also provided for each adverse drug reaction: very common (≥1/10); common (≥1/100, <1/10); uncommon (≥1/1,000, <1/100); rare (≥1/10,000, <1/1,000) very rare (<1/10,000), including isolated reports.
Table 1 Adverse reactions in clinical trials
| Adverse reactions | Frequency category |
| Infections and infestations |
| Laryngitis | Common |
| Ear and labyrinth disorders |
| Tinnitus | Common |
| Respiratory, thoracic, and mediastinal disorders |
| Lung disorder | Very common |
| Rhinitis | Very common |
| Dysphonia | Very common |
| Sputum discoloured | Very common |
| Musculoskeletal and connective tissue disorders |
| Myalgia | Common |
| General disorders and administration site conditions |
| Malaise | Common |
| Investigations |
| Pulmonary function test decreased | Very common |
As the duration of exposure to tobramycin increased over the two open-label extension studies, the incidence of productive cough and pulmonary function test decreased appeared to increase; however, the incidence of dysphonia appeared to decline. Overall, the incidence of adverse events related to the following MedDRA System Organ Class (SOC) decreased with increasing exposure to tobramycin: Respiratory, thoracic, and mediastinal disorders, Gastrointestinal disorders, and General disorders and administration site conditions.
Adverse reactions derived from spontaneous reports
Spontaneously reported adverse reactions, presented below, are reported voluntarily and it is not always possible to reliably establish frequency or a causal relationship to drug exposure.
Nervous system disorders
Aphonia, dysgeusia
Ear and labyrinth disorders
Hearing loss
Respiratory, thoracic, and mediastinal disorders
Bronchospasm, oropharyngeal pain, sputum increased, chest pain
Skin and subcutaneous tissue disorders
Hypersensitivity, pruritus, urticaria, rash
General disorders and administration site conditions
Decreased appetite
In open label studies and post-marketing experience, some patients with a history of prolonged previous or concomitant use of intravenous aminoglycosides have experienced hearing loss (see 4.4). Parenteral aminoglycosides have been associated with hypersensitivity, ototoxicity and nephrotoxicity (see 4.3, 4.4).
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 at: www.mhra.gov.uk/yellowcard.