As with all therapeutic proteins, there is potential for immunogenicity. The detection of antibody formation is highly dependent on the sensitivity and specificity of the assay. Additionally, the observed incidence of antibody (including neutralizing antibody) positivity in an assay may be influenced by several factors including assay methodology, sample handling, timing of sample collection, concomitant medications, and underlying disease. For these reasons, comparison of the incidence of antibodies to RITUXAN HYCELA and rituximab in the studies described below with the incidence of antibodies in other studies or to other products may be misleading.
In the SABRINA study, where previously untreated patients with follicular lymphoma were treated with RITUXAN HYCELA or rituximab in combination with CVP or CHOP, the incidence of treatment-induced/enhanced anti-rituximab antibodies in the RITUXAN HYCELA group was similar to that observed in the rituximab group (2.0% RITUXAN HYCELA vs. 1.9% rituximab). The incidence of treatment-induced/enhanced anti-recombinant human hyaluronidase antibodies was 15% in the RITUXAN HYCELA group compared with 8% in the rituximab group, and the overall proportion of patients found to have anti-recombinant human hyaluronidase antibodies remained generally constant over the follow-up period in both cohorts. All patients who tested positive for anti-recombinant human hyaluronidase antibodies at any point during the study were negative for neutralizing antibodies.
In the SAWYER study, where previously untreated patients with CLL were treated with RITUXAN HYCELA or rituximab in combination with FC, the incidence of treatment-induced/enhanced anti-rituximab antibodies was 12% in the RITUXAN HYCELA group and 15% in the rituximab group. The incidence of treatment-induced/enhanced anti-recombinant human hyaluronidase antibodies was 11% in the RITUXAN HYCELA treatment arm. None of the patients who tested positive for anti-recombinant human hyaluronidase antibodies tested positive for neutralizing antibodies.
The clinical relevance of the development of anti-rituximab or anti-recombinant human hyaluronidase antibodies after treatment with RITUXAN HYCELA is not known.
The following adverse reactions have been identified during post-approval use of rituximab-containing products. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.
- Hematologic: prolonged pancytopenia, marrow hypoplasia, Grade 3–4 prolonged or late-onset neutropenia, hyperviscosity syndrome in Waldenstrom’s macroglobulinemia, prolonged hypogammaglobulinemia
- Cardiac: fatal cardiac failure
- Immune/Autoimmune Events: uveitis, optic neuritis, systemic vasculitis, pleuritis, lupus-like syndrome, serum sickness, polyarticular arthritis, and vasculitis with rash.
- Infection: viral infections, including progressive multifocal leukoencephalopathy (PML), increase in fatal infections in HIV-associated lymphoma, and a reported increased incidence of Grade 3 and 4 infections
- Neoplasia: disease progression of Kaposi’s sarcoma.
- Skin: severe mucocutaneous reactions, pyoderma gangrenosum (including genital presentation).
- Gastrointestinal: bowel obstruction and perforation.
- Pulmonary: fatal bronchiolitis obliterans and fatal interstitial lung disease.
Based on human data, rituximab-containing products can cause fetal harm due to B-cell lymphocytopenia in infants exposed to rituximab in-utero (see Clinical Considerations). There are no available data on RITUXAN HYCELA use in pregnant women to inform a drug-associated risk of major birth defects and miscarriage. In animal reproduction studies, intravenous administration of a rituximab product to pregnant cynomolgus monkeys during the period of organogenesis caused lymphoid B cell depletion in the newborn offspring at doses resulting in 80% of the exposure (based on AUC) of those achieved following a dose of 2 grams in humans. Reduced fetal weight and increased fetal lethality were observed following subcutaneous administration of hyaluronidase human in mice at a dose > 2700 times higher than the human dose. Comparable systemic exposure levels could occur in a pregnant patient following accidental intravenous administration of an entire vial of RITUXAN HYCELA (see Data). Advise pregnant women of the potential risk to a fetus.
The estimated background risk of major birth defects and miscarriage for the indicated populations is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. The estimated background risk in the U.S. general population of major birth defects is 2%–4% and of miscarriage is 15%–20% of clinically recognized pregnancies.
Fetal/Neonatal Adverse Reactions
Observe newborns and infants for signs of infection and manage accordingly.
Postmarketing data indicate that B-cell lymphocytopenia generally lasting less than 6 months can occur in infants exposed to rituximab in-utero. Rituximab was detected postnatally in the serum of infants exposed in-utero.
RITUXAN HYCELA for subcutaneous injection contains rituximab and hyaluronidase human [see Description (11)].
- An embryo-fetal developmental toxicity study was performed on pregnant cynomolgus monkeys. Pregnant animals received rituximab via the intravenous route during early gestation (organogenesis period; post coitum days 20 through 50). Rituximab was administered as loading doses on post coitum (PC) Days 20, 21 and 22, at 15, 37.5 or 75 mg/kg/day, and then weekly on PC Days 29, 36, 43 and 50, at 20, 50 or 100 mg/kg/week. The 100 mg/kg/week dose resulted in 80% of the exposure (based on AUC) of those achieved following a dose of 2 grams in humans. Rituximab crosses the monkey placenta. Exposed offspring did not exhibit any teratogenic effects but did have decreased lymphoid tissue B cells.
- A subsequent pre-and postnatal reproductive toxicity study in cynomolgus monkeys was completed to assess developmental effects including the recovery of B cells and immune function in infants exposed to rituximab in utero. Animals were treated with a loading dose of 0, 15, or 75 mg/kg every day for 3 days, followed by weekly dosing with 0, 20, or 100 mg/kg dose. Subsets of pregnant females were treated from PC Day 20 through postpartum Day 78, PC Day 76 through PC Day 134, and from PC Day 132 through delivery and postpartum Day 28. Regardless of the timing of treatment, decreased B cells and immunosuppression were noted in the offspring of rituximab-treated pregnant animals. The B-cell counts returned to normal levels, and immunologic function was restored within 6 months postpartum.
- In an embryo-fetal study, mice have been dosed daily by subcutaneous injection during the period of organogenesis with hyaluronidase human at dose levels up to 2,200,000 U/kg, which is > 2700 times higher than the human dose. The study found no evidence of teratogenicity. Reduced fetal weight and increased numbers of fetal resorptions were observed, with no effects found at a daily dose of 360,000 U/kg, which is > 450 times higher than the human dose.
- In a peri-and post-natal reproduction study, mice have been dosed daily by subcutaneous injection, with hyaluronidase human from implantation through lactation and weaning at dose levels up to 1,100,000 U/kg, which is > 1,300 times higher than the human dose. The study found no adverse effects on sexual maturation, learning and memory or fertility of the offspring.
There are no data on the presence of hyaluronidase human in human milk or the effect of rituximab on milk production, and there is limited data on the effect of rituximab on the breastfed child. However, rituximab is detected in the milk of lactating cynomolgus monkeys and maternal IgG is present in human breast milk. Rituximab has also been reported to be excreted at low concentrations in human breast milk. Given that the clinical significance of this finding for children is not known, advise women not to breastfeed during treatment with RITUXAN HYCELA and for 6 months after the last dose due to the potential for serious adverse reactions in breastfed children.
Rituximab-containing products can cause fetal harm [see Use in Specific Populations (8.1)].
Verify pregnancy status in females of reproductive potential prior to initiating RITUXAN HYCELA.
Advise females of reproductive potential to use effective contraception during treatment with RITUXAN HYCELA and for 12 months after the last dose of rituximab-containing products, including RITUXAN HYCELA.
All MedLibrary.org resources are included in as near-original form as possible, meaning that the information from the original provider has been rendered here with only typographical or stylistic modifications and not with any substantive alterations of content, meaning or intent.