THE FIRST COST-EFFECTIVENESS ANALYSIS OF DOXECITINE AND DOXRIBTIMINE FOR THE TREATMENT OF THYMIDINE KINASE 2 DEFICIENCY (TK2D)
Author(s)
Uffe Ploug, MSc1, Yasmin Bappoo, MSc2, Caroline Barwood, MSc2, Theo Holland, BSc2, Jessica Dempsey, BSc2.
1UCB, Copenhagen, Denmark, 2Acumetis, London, United Kingdom.
1UCB, Copenhagen, Denmark, 2Acumetis, London, United Kingdom.
OBJECTIVES: Thymidine kinase 2 deficiency (TK2d) is an ultra-rare, life-threatening genetic mitochondrial disorder causing increased risk of early death, progressive muscle weakness, respiratory failure, difficulty swallowing and loss of mobility. Doxecitine and doxribtimine is the first approved therapy for TK2d in patients with age of symptom onset ≤12 years. However some patients may currently still only receive supportive care (SC). There are no existing cost-effectiveness models (CEMs) for TK2d, therefore, we aimed to design the first global TK2d CEM.
METHODS: A Markov model in MS Excel was developed with six states based on motor function, ventilatory support and mortality. The structure captured the progressive natural history of TK2d and the effect of treatment on decline. Doxecitine and doxribtimine was modelled against SC, using data from the clinical program: (MT-1621-101 [NCT03701568] and TK0102 [NCT03845712]), structured expert elicitation, and supporting disease analogue datasets (spinal muscular atrophy, Duchenne-muscular dystrophy and Pompe disease). Direct utility inputs for TK2d are limited, thus, the model incorporated the best available utility evidence from analogue utilities, which were mapped to TK2d health states. The utility values were clinically validated and quality of life (QoL) impact aligned to patient reported experience.
RESULTS: This model suggests that patients receiving doxecitine and doxribtimine gain substantially more quality adjusted life years (QALYs) (>30 undiscounted QALYs) than patients receiving SC alone. The QALY benefit is driven by improved survival, delayed disease progression to severe health states, perceived benefit of receiving treatment, impact on caregiver QoL and preservation or regain of motor and respiratory function. Reducing the need for ventilation particularly has a substantial benefit on QoL. Sensitivity analyses demonstrated that the CEM results were most sensitive to the number of carers and patient utility for the ambulatory state.
CONCLUSIONS: Doxecitine and doxribtimine can provide substantial QALY benefit to patients with TK2d compared with untreated patients.
METHODS: A Markov model in MS Excel was developed with six states based on motor function, ventilatory support and mortality. The structure captured the progressive natural history of TK2d and the effect of treatment on decline. Doxecitine and doxribtimine was modelled against SC, using data from the clinical program: (MT-1621-101 [NCT03701568] and TK0102 [NCT03845712]), structured expert elicitation, and supporting disease analogue datasets (spinal muscular atrophy, Duchenne-muscular dystrophy and Pompe disease). Direct utility inputs for TK2d are limited, thus, the model incorporated the best available utility evidence from analogue utilities, which were mapped to TK2d health states. The utility values were clinically validated and quality of life (QoL) impact aligned to patient reported experience.
RESULTS: This model suggests that patients receiving doxecitine and doxribtimine gain substantially more quality adjusted life years (QALYs) (>30 undiscounted QALYs) than patients receiving SC alone. The QALY benefit is driven by improved survival, delayed disease progression to severe health states, perceived benefit of receiving treatment, impact on caregiver QoL and preservation or regain of motor and respiratory function. Reducing the need for ventilation particularly has a substantial benefit on QoL. Sensitivity analyses demonstrated that the CEM results were most sensitive to the number of carers and patient utility for the ambulatory state.
CONCLUSIONS: Doxecitine and doxribtimine can provide substantial QALY benefit to patients with TK2d compared with untreated patients.
Conference/Value in Health Info
2026-11, ISPOR Europe 2026, Vienna, Austria
Value in Health, Volume 29, Issue 12S
Code
EE254
Topic
Economic Evaluation
Disease
Rare & Orphan Diseases