There is no requirement to use an in-line filter during Mabthera adminstration.[1] Use of an in-line filter is optional.

Use of a 0.2 μm in-line filter was assessed in internal in-use stability studies.[2] MabThera IV solution diluted to concentrations between 0.5 mg/mL and 4 mg/mL remained stable with or without the use an of in-line filter. MabThera met the USP specifications for particulates for single dose, large volume infusion without the use of an in-line filter.

Two studies in the literature report the use of a 0.22 μm in-line filter to administer MabThera infusions diluted to a maximum concentration of 1 mg/mL.[3,4] Study results suggest that the use of an in-line filter would not anticipate any issues.

Yamanouchi et al. evaluated the drug adsorption of pediatric doses of rituximab with 0.2 μm endotoxin-retentive in-line filter use.[5] Study results showed the usefulness of one point masuresurement method of pediatric dose and UV spectrophotometry for filterability test of in-line filters.

1. Roche Internal Regulatory Document (Accessed on 24Jul23).
2. Roche Internal Clinical Study Report (Accessed on 29 Jun 2023).
3. Piro L, White C, Grillo-López A, et al. Extended Rituximab (anti-CD20 monoclonal antibody) therapy for relapsed or refractory low-grade or follicular non-Hodgkin's lymphoma. Ann Oncol 1999;10:655-61. https://www.ncbi.nlm.nih.gov/pubmed/10442187
4. McLaughlin P, Grillo-López A, Link B, et al. Rituximab chimeric anti-CD20 monoclonal antibody therapy for relapsed indolent lymphoma: half of patients respond to a four-dose treatment program. J Clin Oncol 1998;16:2825-33. https://www.ncbi.nlm.nih.gov/pubmed/9704735
5. Yamanouchi T, Horiuchi K, Ishii K, et al. [Usefulness of one point measurement method of pediatric dose and UV spectrophotometry for filterability test of in-line filter]. Yakugaku Zasshi 2014;134:671-7. https://www.ncbi.nlm.nih.gov/pubmed/24790051