The use of locally‐delivered doxycycline in the treatment of periodontitis. Clinical results*

The clinical safety and effectiveness of a subgingivally delivered biodegradable drug delivery system containing doxycycline hyclate (DH) has been evaluated in 3 large 9-month multicenter randomized parallel-design controlled clinical trials. A total of 1002 patients having at least 2 quadrants with a minimum of 4 qualifying pockets > or = 5 mm that bled on probing were enrolled. Each subject had > or = 7 mm probing depths in 2 of the qualifying pockets. Study 1 (n=180) compared DH to sanguinarine chloride (SC) and vehicle control (VC). Study 2 (n=411) and study 3 (n=411) compared DH to VC, scaling and root planing (SRP), and oral hygiene (OH). Clinical measurements included probing depth reduction (PDR), attachment level gain (ALG), bleeding on probing reduction (BOP) and plaque index (PI). Analysis of efficacy data from these 3 trials show all treatments gave significant positive clinical changes from baseline at most time points. Study 1 results indicate that DH was superior to SC and VC in PDR at all time points. Similar results were obtained for ALG when DH was compared to SC and VC. For BOP reductions, DH was superior to VC at all time points and to SC at months 5 through 9. For DH, mean ALG in deep (> or = 7 mm) pockets was 1.4 mm; mean PDR for DH was 2.6 mm. For moderate (5 to 6 mm) pockets, ALG was 0.8 mm and PDR 1.5 mm. Studies 2 and 3 reported mean month 9 ALG for SRP as 0.7 mm and 0.8 mm, respectively. For DH, ALG was 0.8 mm in both studies 2 and 3. At month 9 in studies 2 and 3, 29% and 31% of DH sites and 27% and 34% of SRP sites showed ALG > or = 2 mm. Probing depth reductions followed the same pattern, with 32% of DH sites and 32% of SRP sites showing > or = 2 mm PD reductions in study 2, and 41% of DH and 43% of SRP sites showing PDR of > or = 2 mm in study 3. Comparisons between DH, VC, and OH treatment groups in studies 2 and 3 showed DH treatment was statistically superior to VC and OH at most time points. Results of these 3 large clinical trials demonstrate that treatment of periodontitis with 10% doxycyline hyclate in a bioabsorbable delivery system is equally as effective as SRP and superior in effect to VC and OH in reducing the clinical signs of adult periodontitis.