OK. Lets not let the study rest there because I went back and had a closer look. It's interesting to compare with the Recell study which had 67% healing of diabetic foot ulcers in patients selected for good limb perfusion
Now take a look at the BTM study
First there is a classification system for peripheral limb ischemia which classifies grades 1-4, with grade 4 being severe ischaemia and a high risk of infection and amputation
https://www.jvascsurg.org/article/S0741-5214(14)02156-9/fulltext
Now the BTM cohort contained 18/22 (78%) stage 4 patients with a high risk of amputation, 4 (17%) were stage 3 and 1 patient stage 1
Of the stage 4 patients 11 (61%) had complete wound healing and 2 retained a chronic wound, 3 required a minor amputation and 2 a major amputation. 3 out of the 4 stage 3 wounds were healed completely along with the 1 stage 1 wound.
" reported systematic review data suggest 12-month major amputation risk of WIfI stage 3 and 4 patients to be 11% and 38% and we have shown amputation rates to be 0% and 11.1%, respectively, this highlights the potential future role that BTM has to play in the paradigm of such patients who may otherwise face amputation"
Overall the BTM cohort had far more severe wounds than the Recell study with only 1 graded as good perfusion. So we are not comparing apples with apples. The BTM group contained almost all rotten apples. No way in the world is Recell going to heal wounds with exposed tendon and bone and most had infection in the 14 days prior to BTM application.
" The higher rate of wound healing observed in the patient cohort with toe pressures
>50 mmHg (good perfusion) aligns with previously reported experiences [
15]; however, this should not detract from the high severity of wounds treated with BTM, represented in this subgroup (Table
1), with 92% of those with a toe pressure >50 mmHg containing wounds
scored as a WIfI wound category two or greater (extensive/deep ulcer, with exposed bone joint or tendon) (Table
1). Whilst severe refractory ischaemia (toe pressures < 30 mmHg post-maximal revascularisation) was prevalent in only 30% (n = 7) of the study cohort, with a majority (n = 6) of these cases hosting severe wounds (WIfI wound severity of 3), 12-month amputation-free survival was 70% (n = 5), suggesting BTM offers some capacity to facilitate amputation prevention in the setting of ischaemia not amendable to further revascularisation. These data highlight that the WIfI classification of our observed cohort Biomedicines 2023, 11, 721 10 of 12 was predominantly driven by high wound severity and, therefore, retain a high risk of wound healing failure, irrespective of perfusion status, reinforcing the positive context of our patient outcomes for which BTM offered a non-autologous off-the-shelf reconstruction solution.
https://www.mdpi.com/2227-9059/11/3/721Looking forward to the outcome of the new BTM trial for DFU.
If the results match this one, then it should be game set and match to BTM.
(20min delay)