Rheumatoid Arthritis (RA) Treatments

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice.

The data described below reflect exposure to rituximab in 3,092 patients, with exposures ranging from a single infusion up to 2 years. Rituximab was studied in both single-arm and controlled trials (n = 356 and n = 2,427). The population included 1,180 patients with low grade or follicular lymphoma, 927 patients with DLBCL, 676 patients with CLL, and 309 patients with another indication. Most NHL patients received rituximab as an infusion of 375 mg/m

CLL patients received rituximab 375 mg/m

The most common adverse reactions of rituximab (incidence greater than or equal to 25%) observed in clinical trials of patients with NHL were infusion-related reactions, fever, lymphopenia, chills, infection, and asthenia.

The most common adverse reactions of rituximab (incidence greater than or equal to 25%) observed in clinical trials of patients with CLL were: infusion-related reactions and neutropenia.

In the majority of patients with NHL, infusion-related reactions consisting of fever, chills/rigors, nausea, pruritus, angioedema, hypotension, headache, bronchospasm, urticaria, rash, vomiting, myalgia, dizziness, or hypertension occurred during the first rituximab infusion. Infusion-related reactions typically occurred within 30 to 120 minutes of beginning the first infusion and resolved with slowing or interruption of the rituximab infusion and with supportive care (diphenhydramine, acetaminophen, and intravenous saline). The incidence of infusion-related reactions was highest during the first infusion (77%) and decreased with each subsequent infusion

Serious infections (NCI-CTCAE Grade 3 or 4), including sepsis, occurred in less than 5% of patients with NHL in the single-arm studies. The overall incidence of infections was 31% (bacterial 19%, viral 10%, unknown 6%, and fungal 1%)

In randomized, controlled studies where rituximab was administered following chemotherapy for the treatment of follicular or low-grade NHL, the rate of infection was higher among patients who received rituximab. In diffuse large B-cell lymphoma patients, viral infections occurred more frequently in those who received rituximab.

In patients with NHL receiving rituximab monotherapy, NCI-CTC Grade 3 and 4 cytopenias were reported in 48% of patients. These included lymphopenia (40%), neutropenia (6%), leukopenia (4%), anemia (3%), and thrombocytopenia (2%). The median duration of lymphopenia was 14 days (range, 1−588 days) and of neutropenia was 13 days (range, 2−116 days). A single occurrence of transient aplastic anemia (pure red cell aplasia) and two occurrences of hemolytic anemia following rituximab therapy occurred during the single-arm studies.

In studies of monotherapy, rituximab-induced B-cell depletion occurred in 70% to 80% of patients with NHL. Decreased IgM and IgG serum levels occurred in 14% of these patients.

In CLL trials, the frequency of prolonged neutropenia and late-onset neutropenia was higher in patients treated with rituximab in combination with fludarabine and cyclophosphamide (R-FC) compared to patients treated with FC. Prolonged neutropenia is defined as Grade 3-4 neutropenia that has not resolved between 24 and 42 days after the last dose of study treatment. Late-onset neutropenia is defined as Grade 3-4 neutropenia starting at least 42 days after the last treatment dose.

In patients with previously untreated CLL, the frequency of prolonged neutropenia was 8.5% for patients who received R-FC (n = 402) and 5.8% for patients who received FC (n = 398). In patients who did not have prolonged neutropenia, the frequency of late-onset neutropenia was 14.8% of 209 patients who received R-FC and 4.3% of 230 patients who received FC.

For patients with previously treated CLL, the frequency of prolonged neutropenia was 24.8% for patients who received R-FC (n = 274) and 19.1% for patients who received FC (n = 274). In patients who did not have prolonged neutropenia, the frequency of late-onset neutropenia was 38.7% in 160 patients who received R-FC and 13.6% of 147 patients who received FC.

Adverse reactions presented in Table 2 occurred in 356 patients with relapsed or refractory, low-grade or follicular, CD20-positive, B-cell NHL treated in single-arm studies of rituximab administered as a single agent

In these single- arm rituximab studies, bronchiolitis obliterans occurred during and up to 6 months after rituximab infusion.

In NHL Study 4, patients in the R-CVP arm experienced a higher incidence of infusional toxicity and neutropenia compared to patients in the CVP arm. The following adverse reactions occurred more frequently (greater than or equal to 5%) in patients receiving R-CVP compared to CVP alone: rash (17% vs. 5%), cough (15% vs. 6%), flushing (14% vs. 3%), rigors (10% vs. 2%), pruritus (10% vs. 1%), neutropenia (8% vs. 3%), and chest tightness (7% vs. 1%)

In NHL Study 5, detailed safety data collection was limited to serious adverse reactions, Grade greater than or equal to 2 infections, and Grade greater than or equal to 3 adverse reactions. In patients receiving rituximab as single-agent maintenance therapy following rituximab plus chemotherapy, infections were reported more frequently compared to the observation arm (37% vs. 22%). Grade 3-4 adverse reactions occurring at a higher incidence (greater than or equal to 2%) in the rituximab group were infections (4% vs. 1%) and neutropenia (4% vs. less than 1%).

In NHL Study 6, the following adverse reactions were reported more frequently (greater than or equal to 5%) in patients receiving rituximab following CVP compared to patients who received no further therapy: fatigue (39% vs. 14%), anemia (35% vs. 20%), peripheral sensory neuropathy (30% vs. 18%), infections (19% vs. 9%), pulmonary toxicity (18% vs. 10%), hepato-biliary toxicity (17% vs. 7%), rash and/or pruritus (17% vs. 5%), arthralgia (12% vs. 3%), and weight gain (11% vs. 4%). Neutropenia was the only Grade 3 or 4 adverse reaction that occurred more frequently (greater than or equal to 2%) in the rituximab arm compared with those who received no further therapy (4% vs. 1%)

In NHL Studies 7 (NCT00003150) and 8

In NHL Study 8, a review of cardiac toxicity determined that supraventricular arrhythmias or tachycardia accounted for most of the difference in cardiac disorders (4.5% for R-CHOP vs. 1.0% for CHOP).

The following Grade 3 or 4 adverse reactions occurred more frequently among patients in the R-CHOP arm compared with those in the CHOP arm: thrombocytopenia (9% vs. 7%) and lung disorder (6% vs. 3%). Other Grade 3 or 4 adverse reactions occurring more frequently among patients receiving R-CHOP were viral infection (NHL Study 8), neutropenia (NHL Studies 8 and 9 (NCT00064116)), and anemia (NHL Study 9).

The data below reflect exposure to rituximab in combination with fludarabine and cyclophosphamide in 676 patients with CLL in CLL Study 1 (NCT00281918) or CLL Study 2 (NCT00090051)

Infusion-related adverse reactions were defined by any of the following adverse events occurring during or within 24 hours of the start of infusion: nausea, pyrexia, chills, hypotension, vomiting, and dyspnea.

In CLL Study 1, the following Grade 3 and 4 adverse reactions occurred more frequently in R-FC-treated patients compared to FC-treated patients: infusion-related reactions (9% in R-FC arm), neutropenia (30% vs. 19%), febrile neutropenia (9% vs. 6%), leukopenia (23% vs. 12%), and pancytopenia (3% vs. 1%).

In CLL Study 2, the following Grade 3 or 4 adverse reactions occurred more frequently in R-FC-treated patients compared to FC-treated patients: infusion-related reactions (7% in R-FC arm), neutropenia (49% vs. 44%), febrile neutropenia (15% vs. 12%), thrombocytopenia (11% vs. 9%), hypotension (2% vs. 0%), and hepatitis B (2% vs. < 1%). Fifty-nine percent of R-FC-treated patients experienced an infusion-related reaction of any severity.

The data presented below reflect the experience in 2,578 RA patients treated with rituximab in controlled and long-term studies

Among all exposed patients, adverse reactions reported in greater than 10% of patients include infusion-related reactions, upper respiratory tract infection, nasopharyngitis, urinary tract infection, and bronchitis.

In placebo-controlled studies, patients received 2 × 500 mg or 2 × 1,000 mg intravenous infusions of rituximab or placebo, in combination with methotrexate, during a 24-week period. From these studies, 938 patients treated with rituximab (2 × 1,000 mg) or placebo have been pooled (see

In the rituximab RA pooled placebo-controlled studies, 32% of rituximab-treated patients experienced an adverse reaction during or within 24 hours following their first infusion, compared to 23% of placebo-treated patients receiving their first infusion. The incidence of adverse reactions during the 24-hour period following the second infusion, rituximab or placebo, decreased to 11% and 13%, respectively. Acute infusion-related reactions (manifested by fever, chills, rigors, pruritus, urticaria/rash, angioedema, sneezing, throat irritation, cough, and/or bronchospasm, with or without associated hypotension or hypertension) were experienced by 27% of rituximab-treated patients following their first infusion, compared to 19% of placebo-treated patients receiving their first placebo infusion. The incidence of these acute infusion-related reactions following the second infusion of rituximab or placebo decreased to 9% and 11%, respectively. Serious acute infusion-related reactions were experienced by less than 1% of patients in either treatment group. Acute infusion-related reactions required dose modification (stopping, slowing, or interruption of the infusion) in 10% and 2% of patients receiving rituximab or placebo, respectively, after the first course. The proportion of patients experiencing acute infusion-related reactions decreased with subsequent courses of rituximab. The administration of intravenous glucocorticoids prior to rituximab infusions reduced the incidence and severity of such reactions, however, there was no clear benefit from the administration of oral glucocorticoids for the prevention of acute infusion-related reactions. Patients in clinical studies also received antihistamines and acetaminophen prior to rituximab infusions.

In the pooled, placebo-controlled studies, 39% of patients in the rituximab group experienced an infection of any type compared to 34% of patients in the placebo group. The most common infections were nasopharyngitis, upper respiratory tract infections, urinary tract infections, bronchitis, and sinusitis.

The incidence of serious infections was 2% in the rituximab-treated patients and 1% in the placebo group.

In the experience with rituximab in 2,578 RA patients, the rate of serious infections was 4.31 per 100 patient years. The most common serious infections (greater than or equal to 0.5%) were pneumonia or lower respiratory tract infections, cellulitis and urinary tract infections. Fatal serious infections included pneumonia, sepsis and colitis. Rates of serious infection remained stable in patients receiving subsequent courses. In 185 rituximab-treated RA patients with active disease, subsequent treatment with a biologic DMARD, the majority of which were TNF antagonists, did not appear to increase the rate of serious infection. Thirteen serious infections were observed in 186.1 patient years (6.99 per 100 patient years) prior to exposure and 10 were observed in 182.3 patient years (5.49 per 100 patient years) after exposure.

In the pooled, placebo-controlled studies, the proportion of patients with serious cardiovascular reactions was 1.7% and 1.3% in the rituximab and placebo treatment groups, respectively. Three cardiovascular deaths occurred during the double-blind period of the RA studies including all rituximab regimens (3/769 = 0.4%) as compared to none in the placebo treatment group (0/389).

In the experience with rituximab in 2,578 RA patients, the rate of serious cardiac reactions was 1.93 per 100 patient years. The rate of myocardial infarction (MI) was 0.56 per 100 patient years (28 events in 26 patients), which is consistent with MI rates in the general RA population. These rates did not increase over three courses of rituximab.

Since patients with RA are at increased risk for cardiovascular events compared with the general population, patients with RA should be monitored throughout the infusion and RIABNI should be discontinued in the event of a serious or life-threatening cardiac event.

In the pooled, placebo-controlled studies, newly-occurring hypophosphatemia (less than 2.0 mg/dL) was observed in 12% (67/540) of patients on rituximab versus 10% (39/398) of patients on placebo. Hypophosphatemia was more common in patients who received corticosteroids. Newly-occurring hyperuricemia (greater than 10 mg/dL) was observed in 1.5% (8/540) of patients on rituximab versus 0.3% (1/398) of patients on placebo.

In the experience with rituximab in RA patients, newly-occurring hypophosphatemia was observed in 21% (528/2570) of patients and newly-occurring hyperuricemia was observed in 2% (56/2570) of patients. The majority of the observed hypophosphatemia occurred at the time of the infusions and was transient.

In the experience with rituximab in RA patients, 2,578 patients have been exposed to rituximab and have received up to 10 courses of rituximab in RA clinical trials, with 1,890, 1,043, and 425 patients having received at least two, three, and four courses, respectively. Most of the patients who received additional courses did so 24 weeks or more after the previous course and none were retreated sooner than 16 weeks. The rates and types of adverse reactions reported for subsequent courses of rituximab were similar to rates and types seen for a single course of rituximab.

In RA Study 2, where all patients initially received rituximab, the safety profile of patients who were retreated with rituximab was similar to those who were retreated with placebo

The data presented below from GPA/MPA Study 1 (NCT00104299) reflect the experience in 197 adult patients with active GPA and MPA treated with rituximab or cyclophosphamide in a single controlled study, which was conducted in two phases: a 6-month randomized, double-blind, double-dummy, active-controlled remission induction phase and an additional 12-month remission maintenance phase

Adverse reactions presented below in Table 4 were adverse events which occurred at a rate of greater than or equal to 10% in the rituximab group. This table reflects experience in 99 GPA and MPA patients treated with rituximab, with a total of 47.6 patient-years of observation and 98 GPA and MPA patients treated with cyclophosphamide, with a total of 47.0 patient-years of observation. Infection was the most common category of adverse events reported (47-62%) and is discussed below.

Infusion-related reactions in GPA/MPA Study 1 were defined as any adverse event occurring within 24 hours of an infusion and considered to be infusion-related by investigators. Among the 99 patients treated with rituximab, 12% experienced at least one infusion-related reaction, compared with 11% of the 98 patients in the cyclophosphamide group. Infusion-related reactions included cytokine release syndrome, flushing, throat irritation, and tremor. In the rituximab group, the proportion of patients experiencing an infusion-related reaction was 12%, 5%, 4%, and 1% following the first, second, third, and fourth infusions, respectively. Patients were pre-medicated with antihistamine and acetaminophen before each rituximab infusion and were on background oral corticosteroids which may have mitigated or masked an infusion-related reaction; however, there is insufficient evidence to determine whether premedication diminishes the frequency or severity of infusion-related reactions.

In GPA/MPA Study 1, 62% (61/99) of patients in the rituximab group experienced an infection of any type compared to 47% (46/98) patients in the cyclophosphamide group by Month 6. The most common infections in the rituximab group were upper respiratory tract infections, urinary tract infections, and herpes zoster.

The incidence of serious infections was 11% in the rituximab-treated patients and 10% in the cyclophosphamide treated patients, with rates of approximately 25 and 28 per 100 patient-years, respectively. The most common serious infection was pneumonia.

Hypogammaglobulinemia (IgA, IgG or IgM below the lower limit of normal) has been observed in patients with GPA and MPA treated with rituximab in GPA/MPA Study 1. At 6 months, in the rituximab group, 27%, 58% and 51% of patients with normal immunoglobulin levels at baseline, had low IgA, IgG and IgM levels, respectively compared to 25%, 50% and 46% in the cyclophosphamide group.

In GPA/MPA Study 2 (NCT00748644), an open-label, controlled, clinical study

The safety profile was consistent with the safety profile for rituximab in RA and GPA and MPA.

In GPA/MPA Study 2, 7/57 (12%) patients in the non-U.S.-licensed rituximab arm reported infusion-related reactions. The incidence of IRR symptoms was highest during or after the first infusion (9%) and decreased with subsequent infusions (less than 4%). One patient had two serious IRRs, two IRRs led to a dose modification, and no IRRs were severe, fatal, or led to withdrawal from the study.

In GPA/MPA Study 2, 30/57 (53%) patients in the non-U.S.-licensed rituximab arm and 33/58 (57%) in the azathioprine arm reported infections. The incidence of all grade infections was similar between the arms. The incidence of serious infections was similar in both arms (12%). The most commonly reported serious infection in the group was mild or moderate bronchitis.

In a long-term observational safety study (NCT01613599), 97 patients with GPA or MPA received treatment with rituximab (mean of 8 infusions [range 1-28]) for up to 4 years, according to physician standard practice and discretion. Majority of patients received doses ranging from 500 mg to 1,000 mg, approximately every 6 months. The safety profile was consistent with the safety profile for rituximab in RA, GPA and MPA.

An open-label, single arm study (NCT01750697) was conducted in 25 pediatric patients 6 years to 17 years of age with active GPA or MPA. The overall study period consisted of a 6-month remission induction phase and a minimum 12-month follow-up phase, up to 54 months. During the remission induction phase, patients received rituximab or non- U.S.-licensed rituximab. During the follow-up phase, rituximab or non-U.S.-licensed rituximab were given at the discretion of the investigator (17 out of 25 patients received this additional treatment). Concomitant treatment with other immunosuppressive therapy was permitted

The safety profile in pediatric GPA and MPA patients was consistent in type, nature and severity with the known safety profile of rituximab in adult patients with RA, GPA and MPA, and PV.

In GPA/MPA Study 4, the proportion of patients experiencing an IRR was 32%, 20%, 12%, and 8% following the first, second, third, and fourth infusions, respectively. The observed symptoms of IRRs were similar to those in adult GPA and MPA patients treated with rituximab.

Serious infections were reported in 7 patients (28%), and included influenza (2 patients [8%]) and lower respiratory tract infection (2 patients [8%]) as the most frequently reported events.

Hypogammaglobulinemia (IgG or IgM below the lower limit of normal), including prolonged hypogammaglobulinemia (defined as Ig levels below lower limit of normal for at least 4 months) was observed in GPA/MPA Study 4. During the overall study period, 18/25 patients (72%) had prolonged low IgG levels, including 15 patients who also had prolonged low IgM. Three patients received treatment with intravenous immunoglobulin.

PV Study 1 (NCT00784589), a randomized, controlled, multicenter open-label study, evaluated the efficacy and safety of non-U.S.-licensed rituximab in combination with short-term prednisone compared to prednisone monotherapy in 90 patients (74 Pemphigus Vulgaris [PV] patients and 16 Pemphigus Foliaceus [PF] patients)

The safety profile of the non-U.S.-licensed rituximab in patients with PV was consistent with that observed in patients with rituximab-treated RA and GPA and MPA

Adverse reactions from PV Study 1 are presented below in Table 5 and were adverse events which occurred at a rate greater than or equal to 5% among PV patients treated with non-U.S.-licensed rituximab and with at least 2% absolute difference in incidence between the group treated with non-U.S.-licensed rituximab and the prednisone monotherapy group up to Month 24. No patients in the group treated with non-U.S.-licensed rituximab withdrew due to adverse reactions. The clinical study did not include sufficient number of patients to allow for direct comparison of adverse reaction rates between treatment groups.

Infusion-related reactions were the most commonly reported adverse drug reactions (58%, 22 patients). All infusion-related reactions were mild to moderate (Grade 1 or 2) except one Grade 3 serious infusion-related reaction (arthralgia) associated with the Month 12 maintenance infusion. The proportion of patients experiencing an infusion-related reaction was 29% (11 patients), 40% (15 patients), 13% (5 patients), and 10% (4 patients) following the first, second, third, and fourth infusions, respectively. No patients were withdrawn from treatment due to infusion-related reactions. Symptoms of infusion-related reactions were similar in type and severity to those seen in RA and GPA and MPA patients

Fourteen patients (37%) in the group treated with non-U.S.-licensed rituximab experienced treatment-related infections compared to 15 patients (42%) in the prednisone group. The most common infections in the group treated with non-U.S.-licensed rituximab were herpes simplex, herpes zoster, bronchitis, urinary tract infection, fungal infection, and conjunctivitis. Three patients (8%) in the group treated with non-U.S.-licensed rituximab experienced a total of 5 serious infections (

In PV Study 2 (NCT02383589), a randomized, double-blind, double-dummy, active-comparator, multicenter study evaluating the efficacy and safety of rituximab compared to mycophenolate mofetil (MMF) in patients with moderate-to-severe PV requiring oral corticosteroids, 67 PV patients received treatment with rituximab (initial 1,000 mg IV on Study Day 1 and a second 1,000 mg IV on Study Day 15 repeated at Weeks 24 and 26) for up to 52 weeks

In PV Study 2, ADR defined as adverse events occurring in greater than or equal to 5% of patients in the rituximab arms and assessed as related are shown in Table 6.

In PV Study 2, IRRs occurred primarily at the first infusion and the frequency of IRRs decreased with subsequent infusions: 17.9%, 4.7%, 3.5% and 3.5% of patients experienced IRRs at the first, second, third, and fourth infusions, respectively. In 11/15 patients who experienced at least one IRR, the IRRs were Grade 1 or 2. In 4/15 patients, Grade greater than or equal to 3 IRRs were reported and led to discontinuation of rituximab treatment; three of the four patients experienced serious [life-threatening] IRRs. Serious IRRs occurred at the first (2 patients) or second (1 patient) infusion and resolved with symptomatic treatment.

In PV Study 2, 42/67 patients (62.7%) in the rituximab arm experienced infections. The most common infections in the rituximab arm were upper respiratory tract infection, nasopharyngitis, oral candidiasis and urinary tract infection. Six patients (9%) in the rituximab arm experienced serious infections.

In PV Study 2, in the rituximab arm, transient decreases in T-cell lymphocytes and phosphorus level were very commonly observed post-infusion. In some cases, treatment of hypophosphatemia was required.

Hypogammaglobulinemia (IgG or IgM below the lower limit of normal), including prolonged hypogammaglobulinemia (defined as Ig levels below lower limit of normal for at least 4 months) was observed in PV Study 2. Based on levels less than LLN measured at Week 16, Week 24, Week 40, and Week 52, 16.4% (11/67) of patients with normal baseline immunoglobulins had prolonged hypogammaglobulinemia (10 patients – IgM, 1 patient – both IgG and IgM) after treatment with rituximab.

The observed incidence of anti-drug antibodies is highly dependent on the sensitivity and specificity of the assay. Differences in assay methods preclude meaningful comparisons of the incidence of anti-drug antibodies in the studies described below with the incidence of anti-drug antibodies in other studies, including those of rituximab or of other rituximab products.

Using an ELISA assay, anti-rituximab antibody was detected in 4 of 356 (1.1%) patients with low-grade or follicular NHL receiving single-agent rituximab. Three of the four patients had an objective clinical response.

A total of 273/2578 (11%) patients with RA tested positive for anti-rituximab antibodies at any time after receiving rituximab. Anti-rituximab antibody positivity was not associated with increased rates of infusion-related reactions or other adverse events. Upon further treatment, the proportions of patients with infusion-related reactions were similar between anti-rituximab antibody positive and negative patients, and most reactions were mild to moderate. Four anti-rituximab antibody positive patients had serious infusion-related reactions, and the temporal relationship between anti-rituximab antibody positivity and infusion-related reaction was variable.

A total of 23/99 (23%) rituximab-treated adult patients with GPA and MPA developed anti-rituximab antibodies by 18 months in GPA/MPA Study 1. The clinical relevance of anti-rituximab antibody formation in rituximab-treated adult patients is unclear. In GPA/MPA Study 4, a total of 4/21 (19%) rituximab-treated pediatric patients with GPA and MPA developed anti-rituximab antibodies during the overall study period (assessed at Month 18).

Using a new ELISA assay, a total of 19/34 (56%) patients with PV, who were treated with non-U.S.-licensed rituximab, tested positive for anti-rituximab antibodies by 18 months in PV Study 1. In PV Study 2, a total of 20/63 (32%) rituximab-treated PV patients tested positive for ADA by week 52 (19 patients had treatment-inducted ADA and 1 patient had treatment-enhanced ADA). The clinical relevance of anti-rituximab antibody formation in rituximab-treated PV patients is unclear.

The following adverse reactions have been identified during post-approval use of rituximab. 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.