In July J&J announced plans to cut up to 4,800 jobs and close several production sites globally as it deals with the challenging environment in which the pharma industry currently find itself.
In doing so, the company hopes to realise savings of between $1.3bn (€0.9bn) and $1.6bn, part of an effort to offset the significant losses when some of its big earners come off patent in the next few years.
In September, the pharma firm's Belgian arm Janssen Pharmaceutica learned its fate, earmarked for 688 layoffs at two of its four sites, comprised of 521 full-time positions and 167 contractors.
A company spokesperson in Belgium told Outsourcing-Pharma.com that a compensation proposal was rejected by the workers on Thursday, hence the trade union initiated today's strike.
According to the spokesperson, the vast majority of employees are currently locked out of all four of the firm's Belgian sites, with the union representatives and protesters blocking the entries.
As a consequence, all operations within the firm have been forced to temporarily caese.
"Nobody can get in, except those few that need to perform certain critical functions such as feeding animals," they said.
The strike is isolated to J&J's Belgian operations, the spokesperson confirmed, adding that they have "no idea" how long the industrial action will continue.
"We will have to wait and see if the two parties can agree to come together and resume talks again to resolve this issue."
Meanwhile, on Thursday J&J revealed further plans to revamp its organisation in a bid to address the "new environment" emerging in human healthcare and broaden the company's interests beyond its 'traditional' focus, and help push growth.
One of the biggest concerns spurring the firm to broaden its horizons is antipsychotic medication Risperdal (risperidone), which last year made up around 18 per cent of the company's pharma sales by bringing in over $4bn, but is facing patent expiry next month, leaving a looming chasm in its pharma revenue stream.
So, by the start of January 2008, J&J plans to have established three entirely new business units.
The new office of strategy and growth will be responsible for identifying opportunities for expansion outside J&J's usual box, focusing on areas that are distinct from those being pursued by its existing businesses but that are a strategic fit for the company.
The firm is also establishing a surgical care group to focus on advancing technologies, solutions and services dedicated to the surgical care sector, and a separate comprehensive care group dedicated to products addressing chronic conditions such as metabolic disorders.