The Western world's first gene-therapy drug is set to go on sale in Germany with a price of €1.1 million ($1.4 million), a new record for a medicine to treat a rare disease.

The sky-high cost of Glybera, from the Dutch biotechnology firm UniQure and its unlisted Italian marketing partner, Chiesi, shows how targeted therapies to fix faulty genes may upend the conventional pharmaceutical business model.

After a quarter of a century of experiments and several setbacks, gene therapy is finally throwing a lifeline to patients by inserting corrective genes into malfunctioning cells — but paying for it poses a challenge.