This set of British guidelines published earlier this year missed out on the very important new class of anti-IL17A inhibitors, which is transforming the AS therapeutic landscape with its efficacy, safety and lower cost in longterm maintenance.
On efficacy, it is possibly even more effective than the anti-TNFs in pain relief and functional improvement, plus the benefits are sustained and appear to improve with time. It is also able to retard progression to spinal fusion (ankylosis), a first in AS treatment. A big deal indeed.
Having to endure at least 6 years of anti-TNF treatment to discern any significant radiographic benefit simply means it does not work great. A lot of damage may have happened in that interval.