Bacteriophage therapy of venous leg ulcers in humans: results of a phase I safety trial

research ▲ J O U R N A L O F WO U N D C A R E VO L 1 8 , N O 6 , J U N E 2 0 0 9 2 3 7 Bacteriophage therapy of venous leg ulcers in humans: results of a phase I safety trial M anaging the bacterial population of a wound presents signifi cant chal- lenges to the practitioner. Chronic wounds commonly contain bio- fi lms.1 However, the phenotype of biofi lm communities is not fully responsive to anti- biotics2 and a growing number of wound pathogens are genotypically resistant to antimicrobials. Novel antimicrobial agents that can overcome these resist- ant bacteria need to be investigated so that better wound management regimens can be developed. Lytic bacteriophages are viruses that infect and lyse (kill) their bacterial hosts. They attach to their hosts and kill them via a complex internal replica- tion and lytic cycle. Lytic bacteriophages were wide- ly used to treat bacterial infections in the fi rst half of the twentieth century, when no serious adverse reactions were reported. Bacteriophage therapy fell out of favour in the West following the advent of antibiotics, but its use has continued, uninterrupted, in some former Soviet countries. In the Republic of Georgia, for example, the use of bacteriophage therapy for managing many types of non-systemic infections is accepted practice. In addition, novel methods of delivering bacteri- ophages, and bacteriophages combined with antibi- otics, have been explored. For example, PhagoBio- Derm (Center for Medical Polymers and Biomaterials, Tbilisi, Republic of Georgia), a phage-based, antibac- terial, wound-healing preparation, has been used for wound management in Georgia with good results.3,4 An extensive review of the use of bacteriophages as antimicrobial agents is available elsewhere.5-7 Although phage therapy is widely used and gener- ally accepted as safe and benefi cial in some parts of the world, very few controlled human trials have investigated it in the West.5 Recent (scarce) reports of the use of phages to treat wound infections have focused on: ● Experimentally infected animals8 ● Humans with chronic, suppurating, bacterial skin infections9 ● Use of PhagoBioDerm in humans.3,4 In short, it appears that bacteriophage therapy is an effective treatment in managing wound infec- tions, including those caused by bacteria resistant to multiple antibiotics.6,7 However, no rigorous, ran- domised, double-blind controlled studies have been conducted to support this. Due to the diverse bacterial species inhabiting chronic wounds,10,11 comprehensive management is diffi cult. Much effort is therefore often directed towards managing certain species, such as antibiot- ic-resistant strains of Pseudomonas aeruginosa and Staphylococcus aureus. The results presented here are of a phase I safety clinical trial of a phage cocktail (WPP-201) in patients with venous leg ulcers (VLUs) with or with- out signs of clinical infection. The cocktail of bacte- riophages used in this study was formulated to spe- cifi cally target individual members of the wound’s bacterial community with the ultimate goal of improving wound outcomes. ● Objective: This phase 1 trial set out to examine the safety of a bacteriophage-based preparation for diffi cult-to-treat wounds. ● Method: The intention-to-treat sample comprised 42 patients with chronic venous leg ulcers (VLUs); 39 patients completed the trial. The ulcers were treated for 12 weeks with either a saline control or bacteriophages targeted against Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli. Follow-up continued until week 24. ● Results: No adverse events were attributed to the study product. No signifi cant difference (p>0.05) was determined between the test and control groups for frequency of adverse events, rate of healing, or frequency of healing. ● Conclusion: This study found no safety concerns with the bacteriophage treatment. Effi cacy of the preparation will need to be evaluated in a phase II effi cacy study. ● Declaration of interest: One of the authors (AS) holds an equity interest in Intralytix. The other authors do not have any interest in commercial activities. chronic venous leg ulcer ; macrophage therapy; safety study D.D. Rhoads,1 MT (ASCP), Laboratory Researcher; R.D. Wolcott,1 MD, Director; M.A. Kuskowski, PhD, Associate Professor, Department of Psychiatry, University of Minnesota, Minneapolis, US; B.M. Wolcott,1 Research Technician; L.S. Ward, PhD, Director of Research, Glanbia Research and Development Center, Twin Falls, Idaho, US; A. Sulakvelidze, PhD, Chief Scientist, Intralytix, Baltimore, Maryland, US. Email: Randy@ RandallWolcott.com Journal of Wound Care.Downloaded from magonlinelibrary.com by 161.112.232.111 on October 6, 2014. For personal use only. No other uses without permission. . All rights reserved. research J O U R N A L O F WO U N D C A R E VO L 1 8 , N O 6 , J U N E 2 0 0 92 3 8 Method This prospective, randomised, controlled, double- blind study involving participants with full-thick- ness VLUs of over 30 days’ duration was performed to evaluate the safety of WPP-201, a bacteriophage cocktail developed by Intralytix. The study was performed during 2007 and 2008 at the Southwest Regional Wound Care Center (Lub- bock, Texas, US), in accordance with the require- ments of the Food and Drug Administration (FDA, investigational new drug 12633) and the Western Institutional Review Board (WIRB, protocol #20061649). Phase I trials are normally conducted on healthy subjects, whereas this sample comprised patients with chronic VLUs with or without clinical signs of infection. Nevertheless, the FDA still considered this a phase 1 trial as it concerned the introduction of a new drug to humans. The study product was applied topically to the wound once a week for 12 weeks. The primary endpoint was complete wound epi- thelialisation. However, the primary goal was to examine the safety of WPP-201. Participants New admissions to the Southwest Regional Wound Care Center with chronic VLUs were recruited into the study after signing informed consent. Patients were enrolled between December 2006 and November 2007. Inclusion and exclusion crite- ria are summarised in Table 1. Randomisation was performed using software to assign patients to either the treatment or control group. We wanted to test the safety of the cocktail in a real-life clinical situation, which would include its use on patients with clinical signs of infection. For this reason, patients with infected wounds were not excluded. Development, production, formulation, prepara- tion and administration of WPP-201 WPP-201 is a bacteriophage-based preparation that aims to promote the healing of infected, diffi cult-to- treat wounds by reducing or eliminating the levels of three common bacterial wound pathogens: Sta- phylococcus aureus, Pseudomonas aeruginosa and Escherichia coli. The preparation contains eight bacteriophages in the Podoviridae and Myoviridae families, which are suspended in sterile phosphate-buffered saline (PBS). The concentration of each component phage in WPP-201 is approximately 1 x 109 plaque-form- ing units per millilitre. It is a pH neutral, clear to opalescent, odourless liquid. All of the phages contained in WPP-201 were orig- inally isolated from the environment. They were not genetically manipulated but were extensively characterised by determining their: ● Plaque morphology ● Taxonomic status ● Protein fi ngerprint profi les (by SDS-PAGE) ● Genomic fi ngerprint profi les (by RFLP) ● Genome homogeneity (by PFGE) ● Full-genome nucleotide sequences. Table 1. Inclusion and exclusion criteria Inclusion criteria Exclusion criteria The patient and his/her legal The patient is under 18 years old guardian or authorised representative must have understood, signed and dated the IRB-approved, informed consent form The patient’s ulcer has healed by 30% or more during the week-long screening period preceding treatment The patient must have a life The patient had a history of alcohol or expectancy of at least one year substance abuse during the previous year which could interfere with study concordance or protocol requirements The patient must exhibit The patient has participated in a clinical haemosiderosis, stasis dermatitis, trial evaluating investigational dermatoliposclerosis or oedema pharmaceuticals or biologics within in the lower extremity on which three months (or devices within 30 days) the wound is located of the study. The one-week screening period would have eliminated any sustained effects of antimicrobial dressings The ulcer must be 1–60cm2 in The patient has a history of receiving any diameter of the following within the last 30 days: systemic corticosteroids exceeding a total daily dose of 20mg, immunosupressants, radiation or chemotherapy. Also, anticipated use of the above will exclude the patient The patient’s ulcer must have been The patient’s values of any of the present for >30 days following are signifi cantly outside normal limits: sodium, glucose, blood urea nitrogen, creatine, calcium, creatine phosphokinase, albumin, total protein, alkaline, phospatase, ALT/AST, haemoglobin or white blood cells The post-debridement ulcer at day 0 The patient is pregnant, lactating or has must be free from necrotic tissue positive serum human chorionic and undermining gonadotropin (hCG) Glycosylated haemoglobin (HbA1C) The patient is allergic to any component must be 20mmHg and an ABPI >0.7 bacteriophage Journal of Wound Care.Downloaded from magonlinelibrary.com by 161.112.232.111 on October 6, 2014. For personal use only. No other uses without permission. . All rights reserved. research J O U R N A L O F WO U N D C A R E VO L 1 8 , N O 6 , J U N E 2 0 0 92 4 0 Characterisation was followed by bioinformatic analysis for the presence of ‘undesirable’ genes (those required for antibiotic resistance or the pro- duction of bacterial toxins). Wounds in the test group were treated with a mix- ture containing 4ml WPP-201 and 46ml sterile saline. Controls received only sterile saline. Once a week for the study duration (12 weeks or until wound healing), the diluted WPP-201 or ster- ile saline was applied (drip rate 200ml/h) via an ultrasonic debridement device (USD) (Sonoca 180, Söring) which debrided the wound (15–30sec/cm2). USD has been described and shown to be effective by Stanicis et al.12 All ulcers in both groups were dressed with: ● Promogran (Systagenix) ● Bovine lactoferrin-containing (1%) and xylitol- containing (5%) topical gel (custom compounded by Swiss-American Products, Carrollton, Texas, US) ● Acticoat (Smith & Nephew) ● Allevyn (Smith & Nephew) ● Three-layer compression bandages. This treatment regimen was based on standard management practices used at the Southwest Regional Wound Care Center. Lactoferrin13 and xyti- ol14 appear to have properties that impair bacterial biofi lm formation. Wolcott et al. reported that the combined use of lactoferrin, xylitol and silver-con- taining dressings was more effective against wound biofi lms than standard dressing regimens.15 Howev- er, lactoferrin has been reported to have antiviral properties,16 although its effect against bacteri- ophages has not been determined. Promogran was used as the primary dressing, with a view to preventing the topical gel, which was applied over it, from coming into direct con- tact with the wound surface and potentially inac- tivating the phage. Promogran was chosen because it breaks down in the wound, and so would allow the topical gel to infi ltrate the wound tissue. It was thought that, by the time this occurred, the WWP-201 would have had its desired effect. Acti- coat was also used as a primary dressing because of its antimicrobial properties. Allevyn was used as the secondary dressing. To comply with the treatment protocol, Prom- ogran was used on all patients, including those with infected wounds. This protocol was deemed accept- able by the FDA and WIRB for use in this phase I trial. We believe that this off-label use of Promogran would not harm patients or delay wound healing. Nevertheless, we would not recommend that Prom- ogran and Acticoat be used on the same wound in the absence of phage treatment. WPP-201 treatment was considered successful in this safety study if signifi cantly more adverse events did not occur in the treatment group compared with the control group. Supportive therapies and dressing changes Antibiotic administration to patients in the test and control groups was permitted if clinical signs of acute wound infection (redness, heat, tenderness, oedema) were observed. All patients received compression therapy begin- ning one week before WPP-201 drug (or control) administration. Dressings were changed three times a week (once during the weekly study visit and twice by visiting nurses), as determined by the investigator. This dressing frequency was standard practice at the wound centre. Data collection and safety evaluation All those involved in data collection (investigator, research coordinator, nurses) received training on the application of treatment and data assessment. The following data were collected: ● Medical history (obtained during the initial visit) ● Occurrence of adverse events (weekly) ● Vital signs (weekly) ● Wound size (using Visitrak [Smith & Nephew]) to measure area and a ruler to measure the deepest depth (weekly) ● Wound photographs (weekly) ● Monitoring of adverse events through patient self- reporting and monitoring laboratory values (weekly) ● Subjective wound assessments for: exudate (mild, moderate, copious; serous, serosanguineous, puru- lent); erythema (mild, moderate, severe); pain (mild, moderate, severe) and granulation tissue formation (0–25%, 26–50%, 51–75%, 76–100%) (weekly) ● Results of laboratory tests, including blood chemistries, blood cell counts and bacterial wound cultures (biweekly). Although the study was not designed as a formal effi cacy study, efforts were also made to determine whether application of WPP-201 positively or nega- tively affected wound healing, as measured by the wounds’ degree of closure by week 12. All participants were evaluated weekly for 12 weeks, and primary endpoint evaluations were per- formed at week 12, with follow-up evaluations at weeks 16 and 24. All participants were questioned about adverse events, new diagnoses, new medica- tions and hospitalisation during the entire course of enrolment. Statistical analysis Initially, we requested more than 40 participants in order to increase the power of the study. However, the FDA requested the number be limited for this initial human safety study, and so an enrolment of approximately 40 participants was agreed. The intention-to-treat groups were considered for all statistical analyses. Group differences in the occur- rence of specifi c adverse events were assessed using References 1 James, G.A., Swogger, E., Wolcott, R. et al. Biofi lms in chronic wounds. Wound Repair Regen 2008; 16: 1, 37-44. 2 Stewart, P.S., Costerton, J.W. Antibiotic resistance of bacteria in biofi lms. Lancet 2001; 14; 9276, 135-138. 3 Jikia, D., Chkhaidze, N., Imedashvili, E. et al. The use of a novel biodegradable preparation capable of the sustained release of bacteriophages and ciprofl oxacin, in the complex treatment of multidrug-resistant Staphylococcus aureus- infected local radiation injuries caused by exposure to Sr90. Clin Exp Dermatol 2005; 30: 1, 23-26. Journal of Wound Care.Downloaded from magonlinelibrary.com by 161.112.232.111 on October 6, 2014. For personal use only. No other uses without permission. . All rights reserved. ▲ research ▲ J O U R N A L O F WO U N D C A R E VO L 1 8 , N O 6 , J U N E 2 0 0 9 2 4 1 Fisher’s exact test. To determine the signifi cance of the difference in the frequency of healing between the test and con- trol groups, a chi-square test was performed.17 This test can compare the percentage of successes between multiple groups. In this case, the successes are participants who healed within the listed time frame. Two tests were performed: the fi rst test con- sidered the healing outcome at 12 weeks (the end of treatment) and the second the healing outcome at 24 weeks (end of follow-up). The null hypothesis was as follows: the percentage of patients who healed in the control group is equivalent to the per- centage of patients who healed in the treatment group. The alternative hypothesis stated that the percentages are not equivalent and, therefore, one group had a superior healing frequency. A confi - dence level of 95% (p research J O U R N A L O F WO U N D C A R E VO L 1 8 , N O 6 , J U N E 2 0 0 92 4 2 Results Enrolment Sixty-fi ve patients were screened. Forty-two were enrolled into the study, of whom 39 (93%) complet- ed the treatment: 21/22 of patients in the control group and 18/20 of patients in the test group. Two test patients who had received WPP-201 dropped out of the study after one and four weeks of treatment for unknown reasons, although no adverse events were reported or observed. Their wound areas increased from 2.2 to 2.6cm2 and 10.1 to 13cm2, respectively. A patient in the control group dropped out after 10 weeks of treatment due to hospitalisation. The control group comprised 10 men and 12 women. The group had a mean age of 60.1 years (SD 11.9), mean wound area of 5.8cm2 (SD 5.9), mean wound depth of 0.3cm2 (SD 0.1), mean transcutane- ous partial pressure of oxygen (TcPO2) of 50.3mmHg (SD 13.6), and a mean ankle brachial pressure index (ABPI) of 0.97 (SD 0.09). The WPP-201 treatment group comprised eight men and 12 women. The group had a mean age of 62.8 years (SD 17.5), mean wound area of 7.3cm2 (SD 7.8), mean wound depth of 0.3cm2 (SD 0.1), a mean TcPO2 of 56.1mmHg (SD 11.5), and a mean ABPI of 1.00 (SD 0.13). Adverse events Adverse events of the intention-to-treat patients are summarised in Table 3. No signifi cant differences in the quantity or quality of those events in the con- trol and test groups were observed. In addition, the topical gel did not adversely affect any of the study participants. Healing frequency In the control group, complete wound epithelialisa- tion occurred in 10 patients (45%) by week 12 and in 17 patients (77%) by weeks 12 or 24. In comparison, in the treatment group, this occurred in eight patients (40%) by week 12 and in 12 patients (60%) by weeks 12 or 24. Wounds were still classifi ed as having healed at week 12 even if they recurred by week 24; this occurred in one patient in each group. The chi-square test was used to compare the per- centages of those healed (complete epithelialisa- tion) in the two groups by week 12. The analysis reveals χ2 is 0.1266. The p value was >0.05, so the difference between the two groups not statistically signifi cant and the null hypothesis cannot therefore be rejected. At week 12, there was no signifi cant dif- ference in healing frequency between the control and test groups. Similarly, the χ2 value was calculated using the data describing the patients at 24 weeks (when χ2 = 1.46323). Again, p>0.10 does not fall in the 95% confi dence range, so the null hypothesis cannot be accepted. According to the analyses, the percentages of healed participants were not signifi cantly different between the treatment and control groups at either 12 or 24 weeks. Healing rate A signifi cant groupXtime interaction effect would indicate that the two treatment groups had different wound healing rates over time (differential wound size reduction over time). When all measurement time points were included, the groupXtime interaction was not signifi cant (p=0.10). The interaction remained non-signifi cant after adjusting for the effects of TcPO2 only (groupXtime interaction, p=0.06) and for the effects of TcPO2, age and gender (groupXtime interaction, p=0.06). When the same three models (unadjusted wound size, wound size adjusted for TcPO2 and wound size adjusted for TcPO2, age and gender) were estimated using only data up to week 12, the groupXtime interaction effects were still non-signifi cant (p=0.19, p=0.66, p=0.64, respectively). Only two participants who completed treatment exhibited an increase in wound size (one in each group). Discussion This is the fi rst report of a FDA-approved, physician- initiated, double-blind, phase I clinical trial of a phage preparation for treating wounds. Our observation that WPP-201 was safe and caused no adverse events was not unexpected given the ubiquity of bacteriophages in most environ- ments, including the human skin, mouth and gas- trointestinal tract,5 and the long history of their safe use in many clinical disciplines, including the treat- ment of infected wounds. The few side-effects reported in previous investi- gations were minor, and seemed to be predominant- ly associated with the use of unpurifi ed phage prepa- rations containing high levels of bacterial byproducts, which are largely absent in this preparation.5 The healing rates in both groups were similar to those previously reported in the literature for com- pression therapy.19 The results of our study suggested that the phages did not deleteriously affect wound healing. Howev- er, it is important to stress that our data cannot be used rigorously to ascertain the effi cacy of WPP-201 because this was not designed as an effi cacy trial. An effi cacy trial with WPP-201 or a similar phage preparation would require a larger sample (for statis- tical power) and wounds containing bacteria sus- ceptible in vitro to the phage preparation, a require- ment that was not part of our phase I trial’s enrolment criteria. Lactoferrin has been reported to possess antiviral 4 Markoishvili, K., Tsitlanadze, G., Katsarava, R. et al. A novel sustained- release matrix based on biodegradable poly(ester amide)s and impregnated with bacteriophages and an antibiotic shows promise in management of infected venous stasis ulcers and other poorly healing wounds. Int J Dermatol 2002; 41: 7, 453-458. 5 Sulakvelidze, A., Kutter, E. Bacteriophage therapy in humans. In: Kutter, E., Sulakvelidze, A. (eds). Bacteriophages: Biology and Application.Boca Raton, FL: CRC Press; 2005, 381-436. 6 Alisky, J., Iczkowski, K., Rapoport, A., Troitsky, N. Bacteriophages show promise as antimicrobial agents. J Infect 1998; 36: 1, 5-15. 7 Sulakvelidze, A., Alavidze, Z., Morris, J.G. Jr. Bacteriophage therapy. Antimicrob Agents Chemother 2001; 45: 3, 649-659. 8 Soothill, J.S. Bacteriophage prevents destruction of skin grafts by Pseudomonas aeruginosa. Burns 1994; 20: 3, 209-211. 9 Cislo, M., Dabrowski, M., Weber-Dabrowska, B., Woyton, A. Bacteriophage treatment of suppurative skin infections. Arch Immunol Ther Exp (Warsz) 1987; 35: 2, 175-183. 10 Dowd, S.E., Wolcott, R.D., Sun, Y. et al. Polymicrobial nature of chronic diabetic foot ulcer biofi lm infections determined using bacterial tag encoded FLX amplicon pyrosequencing (bTEFAP). PLoS ONE 2008a; 3: 10, e3326. 11 Dowd, S.E., Sun, Y., Secor, P.R. et al. Survey of bacterial diversity in chronic wounds using pyrosequencing, DGGE, and full ribosome shotgun sequencing. BMC Microbiol 2008b; 8, 43. 12 Stanisic, M.M., Provo, B. J., Larson, D.L., Kloth, L.C. Wound debridement with 25 kHz ultrasound. Adv Skin Wound Care 2005; 18: 9, 484-490. 13 Singh, P.K., Parsek, M.R., Greenberg, E.P., Welsh, M.J. A component of innate immunity prevents bacterial biofi lm development. Nature 2002; 30: 6888, 522- 555. Journal of Wound Care.Downloaded from magonlinelibrary.com by 161.112.232.111 on October 6, 2014. For personal use only. No other uses without permission. . All rights reserved. research J O U R N A L O F WO U N D C A R E VO L 1 8 , N O 6 , J U N E 2 0 0 9 2 4 3 activity.16 The compatibility of bacteriophages with lactoferrin must be examined before effi cacy studies of phages used concomitantly with lactoferrin can be conducted. In addition, exposing phages to ultrasound may impair their viability, although unpublished prelim- inary studies suggest this is not the case. Notably, an investigation of the impact of ultrasound on a non- enveloped virus demonstrated that 60 minutes of ultrasound caused no signifi cant reduction in viable viral titers.20 A potential concern about using therapeutic phage preparations in the clinical setting is that lyso- genic or transducing phage-contaminated prepara- tions may introduce and transfer ‘undesirable genes’ (such as those encoding bacterial toxins) into the environment. Several bacterial toxin-encoding genes are carried by transducing phages, which may accelerate the genes’ spread among various bacte- ria.21 Phages used for therapeutic purposes, there- fore, should be lytic (non-transducing), so that they cannot transfer genetic material among bacteria, and not contain undesirable genes that could be released into the environment. While developing WPP-201, we determined, using classical criteria,22 that all of its eight component phages were lytic. In addition, all of the phages’ DNA were sequenced to completion, and bioinfor- matics analysis was performed to identify homology with undesirable genes. The phages did not contain nucleotide sequences homologous to the bacterial toxin genes listed in 40 CFR § 725.421, or any other known toxin- or antibi- otic-resistance-encoding genes. Moreover, none of the phages’ genomes contained sequences encoding 16S bacterial ribosomal RNA, the presence of which would suggest prior transduction and indicate the future potential to transduce. As stated above, the preparation’s effi cacy must be determined by separate studies. An important con- sideration for the design of our future phase II effi - cacy trial, and for future applications of phage ther- apy for infected wounds, is the specifi city of phages. Phages will only lyse specifi cally targeted bacteria. Although this makes targeted therapy possible, it also requires that therapeutic phages be carefully selected to effectively target the bacteria affecting the patient. Further research is needed to determine how to identify the most virulent bacterium in a wound, and whether its elimination would encourage the proliferation of other bacteria there. Finally, the effect of phages on the barrier formed by biofi lms also needs investigation. An ideal scenario for using phages therapeuti- cally would be to custom-design an effective phage preparation for each patient, based on the wound’s unique microfl ora. Although the regulatory strate- gy for that approach may be challenging, it is not without precedent. For example, the approach would be similar to that used for annually updating the infl uenza vac- cine based on the antigenicity of the infl uenza strain(s) predominating during that year. Custom-designing of phage cocktails was a com- mon practice in the former Soviet Union and East- ern Europe and is still performed in Georgia. Results obtained using custom-designed cocktails suggested that they were signifi cantly more effective in man- aging infections compared with non-custom- designed preparations.5 Interestingly, the FDA recently approved a phage cocktail (designated LMP-102), for a food safety application (21 CFR Part 172), consisting of six L. monocytogenes-specifi c monophages, each of which could be replaced, if necessary, with new L. monocytogenes phages. This will help keep up with the shift in the bacterial strain population and/or manage the emergence of phage-resistant mutants of the bacterium. The substitutions can be per- formed quickly and would not require additional regulatory approvals, as long as the new phages meet the quality-control criteria. A possible scenario for implementing a similar approach for improving the management of wound infections would be to establish a system for iden- tifying the infecting microfl ora and determining its sensitivity to various component phages. Thus, the most effective phages could be selected and used to treat the individual patient whose wound microfl ora was analysed. It is appropriate to determine whether the con- comitant use of bacteriophage therapy with other antibacterial agents would enhance wound healing. Additionally, further research is needed to identify whether WPP-201 would be indicated for: ● Acutely infected wounds ● Wounds with suspected biofi lms ● Chronic wounds or all wounds. Conclusion Before bacteriophage therapy can be widely used in the West, phage preparations fi rst must be demon- strated to be safe and effective in managing wound infections in formal trials. This phase I trial demonstrated the safety of WPP-201 in participants with chronic wounds. However, its effi cacy in managing infected wounds remains to be demonstrated by rigorously designed clinical trials. However, given the current diffi culties encoun- tered with managing chronic wounds (including the increasing problem of multiple antibiotic-resist- ant bacteria), such efforts seem to be prudent and long overdue. ■ 14 Katsuyama, J., Kobayashi, Y., Ichikawa, H. et al. A novel method to control the balence of skin microfl ora Part 2. A study to assess the effect of a cream containing farnesol and xylitol on atopic dry skin. J Dermatol Sci 2005; 38: 3, 207-213. 15 Wolcott, R.D., Rhoads, D.D. A study of biofi lm- based wound management in subjects with critical limb ischaemia. J Wound Care 2008; 17: 4, 145-155. 16 Valenti, P., Antonini, G. Lactoferrin: an important host defence against microbial and viral attack. Cell Mol Life Sci 2005; 62: 22, 2576-2587. 17 Johnson, R.A. Miller & Freund’s Probability and Statistics for Engineers (7th edn). Pearson Prentice Hall, 2005. 18 Singer, J., Willett, J. Applied Longitudinal Data Analysis: Modeling change and event occurrence. Oxford Press, 2003. 19 Marston, W.A., Carlin, R. E., Passman, M.A. et al. Healing rates and cost effi cacy of outpatient compression treatment for leg ulcers associated with venous insuffi ciency. J Vasc Surg 1999; 30: 3, 491-498. 20 Scherba, G., Weigel, R. M., O’Brien, W.D. Jr. Quantitative assessment of the germicidal effi cacy of ultrasonic energy. Appl Environ Microbiology 1991; 57: 7, 2079-2084. 21 Boyd, F. Bacteriophages: Biology and applications. In: Kutter E, Sulakvelidze A, (eds). CRC Press, 2005. 22 Adams, M. Methods of study bacterial viruses. Bacteriophages. Interscience, 1959. We would like to thank Lisa Morrow at the Southwest Regional Wound Care Center, who coordinated this study, Journal of Wound Care.Downloaded from magonlinelibrary.com by 161.112.232.111 on October 6, 2014. For personal use only. No other uses without permission. . All rights reserved.