Three-fifths of drugs rejected for use on the NHS are subsequently approved once pharmaceutical companies resubmit them on "a more reasonable cost basis", the First Minister has said.
Alex Salmond said firms have an obligation to make drugs available to the NHS "at a cost that can be afforded".
Speaking at First Minister's Questions, Conservative leader Ruth Davidson asked the First Minister "what possible excuse" he has for rejecting a cancer drugs fund, similar to the English scheme of the same name, to make more medicines available.
She cited the drug abiraterone, used to treat dying Lockerbie bomber Abdelbaset al-Megrahi, which reportedly costs £3,000 for a month's supply and was rejected by the Scottish Medicines Consortium (SMC) earlier this week.
Mr Salmond said: "The drug company concerned has indicated that it is going to go back and resubmit. The SMC has the extraordinarily difficult task of judging the efficacy of treatment against the budgetary constraints that inevitably apply in any health service. If the position of the SMC, or NICE (National Institute for Health and Clinical Excellence) for that matter in England, was to accept every submission that came forward, it would be impossible to sustain the drugs budget.
"They have to do it on criteria, and I do think Ruth Davidson should pay attention to what a number of the cancer charities have been saying about the obligations on the drugs companies with new drugs coming forward to try and make them available to the NHS at a cost that can be afforded."
Miss Davidson said that "12,000 people have had their lives extended" through the English fund and asked why the First Minister has chosen to "refuse the same opportunity to cancer sufferers in Scotland".
She said: "The First Minister chose to find £50 million to give free prescriptions to people like himself who can afford to pay for them. But he is choosing not to find a more modest sum to extend and improve the lives of Scots with fatal conditions. Will the First Minister now make a different choice? Will he now, 14 months down the line, after countless premature deaths, reconsider, intervene and support a Scottish cancer drugs fund?"
Mr Salmond said the English fund is not "substantially supported". He cited cancer charities Myeloma UK, Breakthrough Breast Cancer and Macmillan Cancer Support, who said the fund "does not address the root causes of why patients may be denied access to treatment", and Tory MP Pauline Latham, who said "it is not fit for purpose and it is not working for the benefit of patients".
He said: "This chamber did consider the question of the cancer drugs fund and paid attention to the many submissions that we received suggesting that that was not the best way forward. Can I suggest to her that the process that we have in Scotland works effectively. Sixty per cent of the drugs resubmitted on a more reasonable cost basis after initially being turned down by the SMC are then approved."