Amid the boom in the radiopharmaceutical space, peptide-based therapeutics could be set to outmanoeuvre antibody-based counterparts, according to WuXi AppTec’s discovery services vice-president Dr Dave Madge.
“We see a lot of potential to reposition a lot of existing radiotherapeutics that are antibody derived to peptide-based radiotherapeutics,” said Madge while speaking at the ELRIG Drug Discovery conference in London, UK, from 2 to 3 October.
Antibody-based radiopharmaceuticals have been widely employed in cancer therapy. However, only two have been approved by the US Food and Drug Administration (FDA) – Spectrum Pharmaceutical’s Zevalin (90Y-ibritumomab tiuxetan) and GSK’s Bexxar (131I-tositumomab).
Although their high specificity and affinity for target antigens make antibodies a robust carrier for radionuclide delivery, peptide-based alternatives offer other advantages, including tissue penetration and low toxicity.
“A lot of work in this area is moving on from antibody-derived radiotherapeutics and identifying peptide analogs,” Madge said.
Whilst WuXi’s speaker did not elucidate on the company’s plans in the space, hints can be gathered from its recent financial activity. In January 2024, the Chinese biotech announced the commission of two new peptide manufacturing plants – one at its Changzhou facility and another at a new site in Taixing, China. The expansion boosts WuXi’s solid-phase peptide synthesis total reactor volume to 32,000l in response “to a surging global demand for peptide therapeutics”, the company said during the announcement.
WuXi offers “advanced radiopharmaceutical solutions to support drug development”, according to its website.
“We’ve seen many high-profile deals in the last three or four years, such as partnerships and acquisitions…this area is gaining ground and there’s massive potential for accelerating cancer therapy,” Madge explained.
Several big pharma companies have made the radiopharma jump over the past few years, with Bristol Myers Squibb (BMS), Novartis, and Eli Lilly all signing $4.2bn, $1.75bn, and $1.4bn acquisition deals respectively. Madge said the desire to combine radiodiagnostics and radiotherapeutics within the industry has been a key driver of the space’s growth. Known as theranostic radiopharmaceuticals, this approach uses radioactive drugs that combine diagnostic imaging and therapeutic activity to treat diseases.
Last month, Telix Pharmaceuticals paid $230m upfront to acquire US-based radioisotope manufacturer RLS Radiopharmacies to expand its manufacturing footprint in the US.
However, for WuXi, matching the global demand for this area could be curbed by the US BIOSECURE Act. This bill, which passed the House of Representatives last month, would prevent US companies from working with certain Chinese biotech life science companies – WuXi AppTec is one of those implicated. The bill’s future now lies with the Senate, with current ties between drugmakers and Chinse contractors looking precarious.
WuXi called the bill “a pre-emptive and unjustified designation without due process that the company strongly objects to” in a statement.
“We firmly believe that WuXi AppTec has not posed, does not pose, and will not pose a security risk to the US or any other country and it has not been subject to any sanction by the US Government agencies,” the biotech added.
