BACKGROUND: Bacterial vaginosis is a very common vaginal infection. The lack of 
endogenous lactobacilli and overgrowth of pathogens facilitate numerous 
gynecological complications.
METHODS: A phase I dose-ranging safety trial tested the safety, tolerability, 
and acceptability of Lactobacillus crispatus CTV-05 (LACTIN-V) administered by 
vaginal applicator. Twelve healthy volunteers were enrolled in 3 blocks of 4 (5 
x 10, 1 x 10, and 2 x 10 cfu/dose). Each block was randomized in a 3:1 ratio of 
active product to placebo. Participants used study product for 5 consecutive 
days, returned for follow-up on days 7 and 14, and had phone interviews on days 
2 and 35.
RESULTS: All 12 participants took 5 doses and completed study follow-up.Overall, 
45 adverse events (AEs) occurred, of which 31 (69%) were genitourinary (GU) AEs. 
GU AEs appeared evenly distributed between the 3 treatment blocks and between 
LACTIN-V and placebo arms. The most common GU AEs were vaginal discharge in 5 
subjects (42%), abdominal pain in 4 subjects (33%), metrorrhagia in 4 subjects 
(33%), vulvovaginitis in 4 subjects (33%), vaginal candidiasis in 3 subjects 
(25%), and vaginal odor in 3 subjects (25%). Forty-one (91%) AEs were mild 
(grade 1) in severity. All 4 moderate AEs (grade 2) were unrelated to product 
use. No grade 3 or 4 AEs or serious adverse events (SAE) occurred. Laboratory 
parameters and colposcopy findings were within normal limits or clinically 
insignificant. The product was well-tolerated and accepted.
CONCLUSION: All 3 dose levels of LACTIN-V appeared to be safe and acceptable in 
healthy volunteers.