TABLE 4.
Incidence Rates Per 100 Patient-Years and 95% Confidence Intervals for Adverse Events Listed in Postmarketing Experience Section of IFN β-1a SC tiw Prescribing Informationa
| Adverse Event | Study Participants (N = 8,107) IR (95% CI) |
|---|---|
| Autoimmune disorders | |
| Drug-induced lupus erythematosus | 0.25 (0.19-0.33) |
| Autoimmune hepatitis | 0.04 (0.01-0.07) |
| Blood and the lymphatic system disorders | |
| TTP/HUS | 0.63 (0.53-0.75) |
| Pancytopenia | 0.10 (0.06-0.16) |
| Eye disorders | |
| Retinopathy | 0.40 (0.31-0.50) |
| Cotton wool spots | 0.27 (0.20-0.35) |
| Obstruction of retinal artery or vein | 0.04 (0.01-0.07) |
| Central and peripheral nervous system disorder | |
| Hypoesthesia | 0.00 (0.00-0.02) |
| Muscle spasms | 3.31 (3.05-3.58) |
| Parasthesia | 6.69 (6.25-7.16) |
| Musculoskeletal stiffness | 0.72 (0.60-0.85) |
| Difficulty walking | 1.85 (1.66-2.06) |
| Skin and subcutaneous tissue disorders | |
| Erythema multiforme | 0.01 (0.00-0.04) |
| Stevens-Johnson syndrome | 0.00 (0.00-0.02) |
| Injection-site abscess | 1.71 (1.53-1.91) |
| Injection-site cellulitis | 1.71 (1.53-1.91) |
| Injection-site necrosis | 0.01 (0.00-0.03) |
a List of postmarketing adverse events does not include those already presented in Table 2 (i.e., psychiatric disorders [depression, suicide], seizures, and hepatobiliary disorders).
CI = confidence interval; IFN β-1a SC tiw = interferon beta-1a administered subcutaneously 3 times weekly; IR = incidence rate; TTP/HUS = thrombotic thrombocytopenic purpura/hemolytic uremic syndrome.