BUROSUMAB

The PBAC recommended burosumab for the treatment of unresectable tumour induced osteomalacia (TIO), an ultrarare condition caused by certain tumours that lead to low levels of phosphate in the blood (hypophosphatemia) which weakens bones over time. The PBAC noted the high unmet clinical need for treatments for this condition, as current therapies are difficult to take given the side effects and are not always effective. 

The PBAC considered that burosumab was likely superior to conventional therapy (which consists of oral phosphorus and oral calcitriol) at normalising phosphate levels and has a different, but non-inferior, safety profile. The PBAC noted that with normalisation of phosphate levels, the long-term health benefits would potentially include correcting established skeletal damage, reducing pain and fatigue, and improving physical function and quality of life. The PBAC noted this was supported by the sponsor’s hearing before the PBAC which included a testimonial from a patient who experienced substantial quality of life improvements from treatment with burosumab. The PBAC noted input from XLH Australia which described the success of burosumab in X-Linked hypophosphataemia (XLH) patients and strongly supported its potential benefit for people with TIO, who experience a very similar disease burden as those with XLH, including severe bone pain, muscle weakness, fractures, fatigue and long delays to diagnosis. 

The PBAC accepted the submission’s assumption that the incremental costs and benefits of burosumab compared to conventional therapy are likely similar for adult patients with unresectable TIO and XLH, and recommended listing at the same price per vial. The PBAC considered that the estimated financial impact was reasonable and advised that the proposed risk sharing arrangement was adequate to manage uncertainties relating to how long burosumab would be used by patients and the long-term gains in health. 

The PBAC recommended that for patients to be eligible to continue receiving burosumab  they must have achieved normal phosphate levels in the blood or, where an adequate response cannot be demonstrated, the treating physician must confirm that continuing treatment is clinically required by a second specialist physician. The PBAC advised that the requirements for continuing treatment should flow on to the restrictions for XLH.