Antibody-drug conjugates (ADC) are one of the fastest-growing anticancer drugs. BioNTech’s licensed ADC is now in Phase III. According to a report in BioSpace, BioNTech is attempting to compete with Daiichi Sankyo and AstraZeneca’s Enhertu which is already heavily involved in the breast cancer subgroup.
ADC’s partner and creator of ADC’s, DualityBio, has just set the trial schedule. BioTech’s ADC called DB-1303 was approved in April 2023. BioNTech paid DualityBio (China) $170 million for its rights, another $1.5 billion in negotiated payments plus tiered royalties.
Phase III
DB-1303 is a topoisomerase-1 inhibitor (TI) and is being compared to chemotherapy in the Phase III trial for HER2-low and/or HR +metastatic breast cancer patients where the disease has metastasized in spite of having endocrine therapy.
Trial results in Phase ½ showed DB-1303 as well tolerated.
TIs can inhibit cell expansion by preventing DNA replication, stimulating DNA damage, and promoting cell cycle arrest. TIs have been used in chemotherapy to promote an antiproliferative effect but their impact on cancer metastasis is not well known.
Targeted Therapy
Proteins in breast cancer cells enable the cancer cells to spread, grow, and live longer. ADC is a targeted therapy carrying an antibody designed to either destroy cancer cells or slow their growth.
BioNTech and its partner DualityBio’s ADC is anticipated to be a respectable competitor to Daiichi Sankyo and AstraZeneca’s HER2 topoisomerase and antibody inhibitors that are used in the treatment of several types of cancer such as colon cancer, leukemia, ovarian, and small-cell lung cancer.
Blockbuster status
Enhertu retains blockbuster status. Analysts project $2.4 billion in sales at y/e 2024.
The ADC market is and will continue to be strong. Pfizer, BioNTech’s partner in the pandemic market, closed the largest merger and acquisition this year with the purchase of Seagen and three ADCs that were approved earlier this year for $43 million.
DualityBio and BioNTech also added a drug called Trop2. It is an antibody-drug conjugate that has proven efficacy in NSCLC and various solid tumors.
BioNTech was granted rights to the marketing of the drugs globally with the exception of Hong Kong, Macau, and mainland China as DualityBio has commercial rights in those areas.
A Trop-2-directed ADC that has been FDA approved is Gilead’s Trodelvy primarily marketed for breast cancer. Sales were approximately $260 million by the first half of 2023. Analysts project by 2028 sales will hit $2.8 billion.
With the current product decline relating to COVID, BioTech plans to return to focusing on cancer therapeutics. The first two quarters of 2023 brought $1.5 billion in sales as opposed to $10.4 billion for the same period in 2022. The Phase III trial should be completed by August of 2025.
