J&J looks ahead at potential flu therapy after approval of its COVID-19 vaccine

Now that J&J’s COVID-19 vaccine has been approved in the US and the EU, J&J is looking ahead at a new class of drugs as a potential flu therapy.

A deal between Janssen, J&J’s Belgian subsidiary, and Cidara Therapeutics will see Janssen paying $27m upfront for access to a new class of drugs, antiviral conjugates.

Cidara says that the new class of drugs could work against all strains of flu.

Cidara’s CEO Jeffrey Stein says the lead antiviral conjugate, CD388, has the potential to treat and protect against all flu strains with a single dose.

Talking to investors yesterday, Stein said that antiviral conjugates (AVCs) are potent long-acting drugs, so they are different from vaccines and monoclonal antibodies. AVCs are antivirals coupled to a human antibody fragment and are designed to inhibit viral replication while also engaging the immune system.

Cidara plans to file an Investigational New Drug (IND) Application by the end of 2021 and will be responsible for development and manufacturing until phase 2. At that point, Janssen will take over, after reimbursing Cidara for the R&D costs. Janssen will take the candidate through late-stage development and manufacturing.

With current flu vaccines there are two main limitations: they only protect against three or four strains and efficacy is lower in older adults, while some people don’t respond to them at all.

Stein said: “We have yet to find a flu strain that is not susceptible to CD388 at the expected efficacious exposure. So we’re very optimistic that this could be a better solution, especially in times of a pandemic.”

Stein went on to say that Cidara’s AVCs have shown promise in severely immunocompromised mouse infection models, “which are intended to represent high risk populations such as the elderly or immune compromised”.

While vaccines can take up to 14 days to be effective, AVCs are expected to take effect “nearly immediately”, said Stein.

In the call to investors, Stein also said that Cidara could be in line for another $753m for R&D budgeting and milestones, and that tiered royalties could be in the “mid to high single digits”.

COO of Cidara, Paul Daruwala, was also on the call. He said: “What all experts anticipate, and we agree, is that the flu market will return, very similar to the way it has in previous years.”

Stein added: “Before the coronavirus hit last year, the major worry was pandemic influenza. And so that was one of the reasons why we really prioritised our influenza programme.”