OBJECTIVES: Follicular lymphomas (FL) constitute the second most common sub-type of non-Hodgkin lymphoma (NHL), and marginal zone lymphomas (MZL) the third. The introduction of rituximab around 15 years ago has led to a substantial increase in survival for patients with indolent NHLs. With a median overall survival of approximately 14 years and a median first-line progression-free survival of between 2–4 years for most rituximab-based regimens, more patients may require second- and third-line therapies. There is currently limited literature reporting estimates of the number of these patients.

METHODS: We created a model to estimate the number of patients in the EU28 with relapsed and/or refractory FL and MZL requiring a new (LOT) treatment in a given year. Population data from the World Bank, epidemiological data from GLOBOCAN and the literature, and efficacy data from published randomised controlled trials and observational studies, were used to populate the model. Market research data was used to determine the market shares of FL and MZL treatments. The model tracked both prevalent and incident patients between 2017 and 2022.

RESULTS: Across the EU28, the model projects that over the 5-year period, 63,804 FL and 25,560 MZL patients will require a second LOT. Of these, 58,439 FL and 18,606 MZL patients will have relapsed on, or be refractory to, a prior rituximab containing regimen. An estimated 41,936 FL and 15,331 MZL patients will require a third LOT between 2017 and 2022. Of these, 41,443 FL and 14,369 MZL will have been previously treated with a rituximab containing regimen.

CONCLUSIONS: We predict a growing number of patients eligible for second- and third-line therapies in FL and MZL. With improved outcomes from first line therapies, greater consideration must now be given to the relapsed/refractory setting, to consolidate gains in patient survival.