Table 6.

Chemical properties and biological activity of photosensitizers used in clinical trials for inactivation of bacteria

#	PS structure/generic name	Condition	Results
1	RLP068 (PS28) Charge: + 4 MW = 1257 Da	Infected diabetic foot ulcers [194]	Outcome: 2 log CFU reduction compared to placebo, 24 h after one treatment [PS]: 3.5 mM Light dose: 60 J/cm2 (laser λ = 689 ± 5 nm)
2		Infected diabetic ulcers [195]	Outcome: bacterial CFU count close to 0, after 2nd treatment, in 94% of leg ulcers [PS]: n/a Light dose: 60 J/cm2 (λ = 630 nm) − 2 × treatments
3		Infected diabetic ulcers [196]	Outcome: significant ulcer reduction, with decrease of bacterial load over the 2 weeks of treatment [PS]: n/a Light dose: 60 J/cm2 (λ = 630 nm) − 4 × to 6 × treatments
4		Infected diabetic ulcers [197]	Outcome: 40% of the patients completely healed; 28% had ulcer area reduced by > 50%; [PS]: n/a Light dose: 60 J/cm2 (λ = 630 nm) − 4 × to 16 × treatments
5	PPA-904 (PS42) Charge: + 1 MW = 533 Da	Chronic leg and foot diabetic ulcers [198]	Outcome: 0.7 log reduction compared to placebo, immediately after treatment. No difference between treatment and placebo groups 24 h after treatment [PS]: ~ 490 µM Light dose: 50 J/cm2 (CureLight 01™ λ = 570–670 nm)
6	Methylene blue (PS18) + toluidine blue (PS20) Charge: + 1 MW = 284/270 Da	Osteomyelitis (diabetic foot) [199]	Outcome: foot amputation was prevented in 17/18 treatment groups periodontal pathogens versus 0/16 in control group [PS]: ~ 36 mM of each Light dose: 6–30 J/cm2 (light λ = 400–725 nm)
7	Methylene blue (PS18) Charge: + 1 MW = 284 Da	Infected diabetic foot ulcers [200]	Outcome: statistically significant decrease of wound area compared to control group [PS]: ~ 312 µM Light dose: 6 J/cm2 (light λ = 660 nm) − 10 × treatments
8		Infected wounds [201]	Outcome: inactivation of MDR bacteria and wound healing in 5/5 patients [PS]: 31 mM (2 ml) Light dose: 120 J/cm2 (light λ = 635 nm) − multiple treatments
9	MAL: protoporphyrin IX precursor (PS9b) Charge: 0 MW = 145 Da	Single case of chronic venous ulceration infected by S. aureus and E. faecalis [202]	Outcome: clinical improvement and no bacteria detected after treatment [PS]: 160 mg/g MAL cream Light dose: 37 J/cm2 (light λ = 630 nm) − 4 × treatments
10		Chronic leg ulcers [203]	Outcome: all nine patients had complete ulcer healing after 24 weeks [PS]: 275 µM Light dose: 18 J/cm2 (light λ = 630 nm) − 8 × treatments
11	5-ALA: protoporphyrin IX precursor (PS9a) Charge: 0 MW = 131 Da	Chronic skin ulcers in lower limbs infected with P. aeruginosa [204]	Outcome: 2 log CFU reduction compared to placebo, 24 h after one treatment [PS]: 1.5 mM Light dose: 80 J/cm2 (light λ = 630 nm)
12		Infection by Helicobacter pylori [205]	Outcome: greatly reduced infection in treated zones of gastric antrum [PS]: ALA 20 mg/kg (0.15 µmol/kg) Light dose: 50 J/cm2 (laser λ = 410 nm or white light from an Olympus GIF 100 endoscope)