Scottish Conservative leader Ruth Davidson has called for an urgent deal to allow a key breast cancer drug that is offered to patients south of the border to be made available in Scotland.

Perjeta, also known as pertuzumab, has been rejected three times for routine use in the Scottish NHS.

The charity Breast Cancer Now has said the treatment can prolong the lives of women with incurable HER2 positive metastatic breast cancer by up to 16 months.

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Ms Davidson argued that delays in implementing a better system for negotiating on the cost of medicines in Scotland had left Scottish cancer sufferers facing the prospect of moving south to receive treatment.

Speaking at First Minister's Questions at Holyrood, she said: "In Scotland today, women with secondary breast cancer are faced with a choice - they can move home for a chance to live longer, or they can stay put in the knowledge that that chance is denied them here.

"We urgently need a deal on Perjeta and we need to fix the system now."

She continued: "The Health Secretary promised a new system of negotiating on the cost of medicines in December 2016."

Ms Davidson added: "It is now May 2018 - 17 months later - so what is taking this government so long to fix the system to help get access to medicines like Perjeta, and can the First Minister give the exact date that her government will put in place the new negotiating system that she promised, so that we have greater access to treatments that let people live longer and better quality lives."

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Nicola Sturgeon stressed that decisions on making particular medicines available for routine access via NHS Scotland are taken independently by the Scottish Medicines Consortium (SMC).

The consortium rejected the drug, manufactured by Roche, for a third time in June 2017 on the basis it was not cost-effective.

National procurement officials are currently in talks with the manufacturer aimed at achieving a "fair and transparent price", the First Minister said.

She said there was an "ongoing process of implementing reforms" to the procurement process, but added that did not remove the need for "very close consideration of individual applications".

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"These are difficult decisions, and it's right that we support the SMC to take these decisions," she said.

"If what Ruth Davidson is encouraging the company to do is make sure that the price that is being offered to NHS Scotland is as reasonable, fair and transparent as the price that has been offered elsewhere in the UK, then I would certainly endorse that.

"Hopefully the discussions that are under way will lead to exactly that."