A subcutaneous version of Daiichi Sankyo’s AstraZeneca-partnered blockbuster antibody-drug conjugate (ADC) Enhertu could be in the works from Korea’s Alteogen following a licensing deal worth up to $300 million.
Under the deal, Daiichi will pay Alteogen $20 million upfront to develop the subcutaneous (SC) Enhertu formulation using its human hyaluronidase (ALT-B4) platform, according to a Korean exchange disclosure. Commercial and development milestones could add up to another $280 million for Alteogen, plus royalties tied to sales.
The contract is conditional and “may vary” based on the success of clinical studies and regulatory approval.
A new version of Enhertu could provide a boon for Daiichi and AstraZeneca. Over the first half of this year, the drug’s sales stalled out with $893 million in combined sales collected over the second quarter, marking a sequential increase of only 1.6%. AstraZeneca blamed the slowdown partly on a destocking dynamic in China following an inventory buildup in the first quarter.
Meanwhile in England, the country’s National Institute for Health and Care Excellence (NICE) in July turned away Enhertu’s price offering, finding that it falls “above the upper end of the range NICE considers an acceptable use" of NHS England’s resources. That means that about 1,000 patients in England and Wales won’t be able to access the treatment.
As for Alteogen, the company’s ALT-B4 technology was also tapped by Merck in 2020 in a deal that was recently revised from non-exclusive to exclusive. In 2019, the Korean biotech disclosed the contract as one with a “top 10 global pharmaceutical company” and its first global agreement for ALT-B4. Merck was given worldwide rights to the platform for use in multiple products for an initial payment of $13 million and milestones that could total $1.37 billion.
More recently, the contract was edited to allow exclusive worldwide rights to produce subcutaneous versions of Merck’s Keytruda with a down payment of $20 million and up to $432 million in milestone payments, Korea’s Maeil Business Newspaper reported in February.
"The SC product of ADC treatment is undergoing its own research, and overseas ADC companies are also interested in discussing cooperation,” Alteogen CEO Park Soon-jae told the news outlet at the time.
ALT-B4 enables the large volume subcutaneous administration of typically intravenously delivered drugs by temporarily hydrolyzing hyaluronan in the extracellular matrix, according to the company. Elsewhere for Alteogen, the company is also working on biosimilars to Regeneron’s Eylea and Roche’s Herceptin.