Subcutaneous versus intravenous administration of rituximab: pharmacokinetics, CD20 target coverage and B-cell depletion in cynomolgus monkeys

PLoS One. 2013 Nov 12;8(11):e80533. doi: 10.1371/journal.pone.0080533. eCollection 2013.


The CD20-specific monoclonal antibody rituximab (MabThera(®), Rituxan(®)) is widely used as the backbone of treatment for patients with hematologic disorders. Intravenous administration of rituximab is associated with infusion times of 4-6 hours, and can be associated with infusion-related reactions. Subcutaneous administration of rituximab may reduce this and facilitate administration without infusion-related reactions. We sought to determine the feasibility of achieving equivalent efficacy (measured by endogenous B-cell depletion) and long-term durability of CD20 target coverage for subcutaneously administered rituximab compared with intravenous dosing. In these preclinical studies, male cynomolgus monkeys were treated with either intravenous rituximab or novel subcutaneous formulation of rituximab containing human recombinant DNA-derived hyaluronidase enzyme. Peripheral blood samples were analyzed for serum rituximab concentrations, peripheral B-cell depletion, and CD20 target coverage, including subset analysis according to CD21+ status. Distal lymph node B-cell depletion and CD20 target coverage were also measured. Initial peak serum concentrations of rituximab were significantly higher following intravenous administration than subcutaneous. However, the mean serum rituximab trough concentrations were comparable at 2 and 7 days post-first dose and 9 and 14 days post-second dose. Efficacy of B-cell depletion in both peripheral blood and distal lymph nodes was comparable for both methods. In lymph nodes, 9 days after the second dose with subcutaneous and intravenous rituximab, B-cell levels were decreased by 57% and 42% respectively. Similarly, levels of peripheral blood B cells were depleted by >94% for both subcutaneous and intravenous dosing at all time points. Long-term recovery of free unbound surface CD20 levels was similar, and the duration of B-cell depletion was equally sustained over 2 months for both methods. These results demonstrate that, despite initial peak serum drug level differences, subcutaneous rituximab has similar durability, pharmacodynamics, and efficacy compared with intravenous rituximab.

Trial registration: NCT00930514 NCT01200758 NCT01292603.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Intravenous
  • Animals
  • Antibodies, Monoclonal, Murine-Derived / administration & dosage*
  • Antibodies, Monoclonal, Murine-Derived / pharmacokinetics
  • Antigens, CD20 / metabolism
  • Antineoplastic Agents / administration & dosage*
  • Antineoplastic Agents / pharmacokinetics
  • B-Lymphocyte Subsets / metabolism
  • Immunophenotyping
  • Infusions, Subcutaneous
  • Leukocytes, Mononuclear
  • Lymph Nodes / cytology
  • Lymphocyte Depletion
  • Macaca fascicularis
  • Male
  • Receptors, Complement 3d / metabolism
  • Rituximab


  • Antibodies, Monoclonal, Murine-Derived
  • Antigens, CD20
  • Antineoplastic Agents
  • Receptors, Complement 3d
  • Rituximab

Associated data


Grant support

All funding for work was provided by F. Hoffmann-La Roche. While the intended purpose of the study was to evaluate the potential for drug development, the fiscal source had no role in study design, data collection and analysis and preparation of the manuscript which was performed at the independent discretion of the researchers involved. The decision to publish the work was however held until developmental interests were secure.