Abstract
Background
Minocycline is a promising anti-inflammatory and protease inhibitor that is effective in multiple pre-clinical stroke models. We conducted an early phase trial of intravenous (IV) minocycline in acute ischemic stroke.
Methods
Following an open label, dose escalation design, minocycline was administered IV within 6 hours of stroke symptom onset in preset dose tiers of 3, 4.5, 6, or 10 mg/kg daily over 72 hours. Minocycline concentrations for pharmacokinetic analysis were measured in a subset of patients. Subjects were followed for 90 days.
Results
Sixty patients were enrolled, 41 at the highest dose tier of 10 mg/kg. Overall age (65±13.7), race (83% white) and sex (47% female) were consistent across the doses. The mean baseline NIHSS was 8.5±5.8 and 60% received tPA. Minocycline infusion was well tolerated with only 1 dose limiting toxicity at the 10 mg/kg dose. No severe hemorrhages occurred in tPA treated patients. Pharmacokinetic analysis (n=22) revealed a half life of about 24 hours and linearity of parameters over doses.
Conclusions
1.) Minocycline is safe and well tolerated up to doses of 10 mg/kg IV alone and in combination with tPA. 2.) The half life of minocycline is about 24 hours, allowing every 24 hour dosing. 3.) Minocycline may be an ideal agent to use with tPA.
Keywords: ischemic stroke, minocycline, dose-finding, neuroprotection, pharmacokinetics
Minocycline is a broad-spectrum neuroprotective agent with multiple proposed mechanisms of action in a wide variety of injury models.1–5 In addition to being an anti-inflammatory agent, minocycline has been shown to be anti-apoptotic6 and an inhibitor of both PARP (polyadenosine diphosphate ribose polymerase)-1 and the matrix metalloproteinases (MMPs).7,8 Particularly intriguing is the potential for minocycline to be vascular protective and reduce the harmful bleeding effects of tissue plasminogen activator (tPA).9,10
Considering minocycline as a repurposed drug with a known safety profile, we evaluated its safety, tolerability and pharmacokinetics in a dose escalation trial in patients with acute ischemic stroke.
Materials and Methods
This study was an open-label, dose-escalation trial and was approved by the Institutional Review Boards of the Medical College of Georgia, University of Kentucky and the Oregon Health Sciences University and the Food and Drug Administration (see IND 77,796 ; ClinicalTrials.gov identifier NCT0063039) prior to initiation. All patients or their representative were required to give informed consent prior to participation. Inclusion criteria were: 1) over 18 years of age; 2) acute onset focal neurologic deficit consistent with acute ischemic stroke, or computed tomographic scan consistent with acute cerebral ischemia; 3) onset of symptoms less than 6 hours; 4) measurable neurologic deficit (NIHSS >1). The exclusion criteria were: 1) allergy to tetracycline antibiotics; 2) pregnancy or suspected pregnancy (pregnancy test will be done on women of child-bearing potential); 3) hepatic and/or renal insufficiency (LFT’s>3× upper limit of normal; creatinine>2mg/dL); 4) thrombocytopenia (platelet count <75,000/mm3); 5) history of intolerance to minocycline; 6) dizziness at the time of stroke or in the past month (by self-report); 7) aphasia likely to interfere with patients ability to report adverse effects; 8) previous functional disability (modified Rankin > 1); 9) stuporous or comatose; 10) presence of another serious illness likely to confound the study; 11) unlikely to be available for 90 day follow-up; 12) severe stroke (NIHSS>22); 13) undergoing an interventional neuroradiological intervention in first 12 hours. Patients were allowed to have received tPA since no negative effect on in vitro clot lysis was detected over a wide range of concentrations.9
Drug Administration
All patients received an intravenous loading dose of minocycline (MINOCIN – Wyeth Japan), followed by maintenance doses of half the daily dose every twelve hours for a total of 6 doses. Four dose tiers were planned (3, 4.5, 6 and 10 mg/kg daily) and weight –based doses were capped at 270, 315, 420 and 700 mg daily for each of the four tiers. Each dose was reconstituted in 250 mL of Lactated Ringers and infused over one hour.
Pharmacokinetics
In eligible patients enrolled at the Medical College of Georgia, blood samples were drawn for quantification of minocycline serum concentrations. Blood (5 mL) was collected at the end of the initial infusion and at 1, 6, 12, 24, 48 and 72 hours after the last dose. Samples were analyzed using high performance liquid chromatography (HPLC), as previously reported.11,12 Pharmacokinetic parameters were calculated using standard compartmental analysis.
Safety Assessment
Investigators closely monitored each patient for evidence of study drug intolerance, particularly focusing on dizziness, gastrointestinal complaints and infusion reactions. All adverse events were immediately reported to the Safety Officer (FTN) for a decision whether to discontinue the study medication and/or reduce the dose. In addition, daily laboratory tests for assessment of complete blood count (CBC) and serum chemistries were drawn. The Internal Safety Committee reviewed each patient and met weekly. A Data Safety Monitoring Board was appointed by NIH and monitored the study.
Dose Finding Strategy
A modified CRM design13,14 was employed to determine the maximum tolerated dose (MTD) of minocycline. Monitoring of the CRM was performed using software designed by John Cook at MD Anderson (http://biostatistics.mdanderson.org/SoftwareDownload) called CRM based on a Windows platform. Following entering information regarding doses and expected toxicities, results for each patient as they were accrued were entered. The CRM informed as to escalation, de-escalation, or maintenance of the same dose in the subsequent cohort (n=4) of enrolled patients.
Statistical Analysis
Descriptive statistics were calculated for baseline characteristics and all adverse events. Due to the small sample size in the 4.5 mg/kg and 6.0 mg/kg dose tiers, statistical tests for differences in demographic and other baseline characteristics could not be performed. All statistical analyses were performed using SAS 9.2.
Results
Between April 2008 and November, 2009, 60 patients were enrolled. Table 1 gives the demographic and baseline characteristics of the 60 patients enrolled in the study overall and by dose tier. At 90 days, 50% had excellent outcome as determined by a mRS of 0 or 1, with no difference between the dose tiers (Table 1). There were 5 individuals who died during the time of the study andonly 1 was considered as potentially being related to the administration of minocycline and the cause of death was reported as a direct result of the admission infarction. This was the only dose limiting toxicity recorded in the study. Of the other two deaths occurring within hospitalization, the cause of death was listed as an extension of the admission infarction and the other was listed as malignant brain edema from the qualifying infarction. For the two deaths occurring between discharge and 90 days, the cause of death was listed as gastric cancer (presumed) and medical complications or condition due to worsening congestive heart failure.
Table 1.
Patients
| Variable | Level | Overall (n=60) | 3mg/kg (n=11) | 4.5mg/kg (n=4) | 6mg/kg (n=4) | 10mg/kg (n=41) |
|---|---|---|---|---|---|---|
| Age† | 65.0 (13.7) | 61.6 (10.5) | 70.0 (11.4) | 61.3 (9.8) | 65.8 (15.0) | |
| Female†† | 28 (47) | 6 (55) | 3 (75) | 2 (50) | 17 (41) | |
| Race†† | White | 50 (83) | 11 (100) | 3 (75) | 3 (75) | 33 (81) |
| Black | 9 (15) | 0 (0) | 1 (25) | 1 (25) | 7 (17) | |
| Asian | 1 (2) | 0 (0) | 0 (0) | 0 (0) | 1 (2) | |
| Weight in kg† | 81.6 (21.6) | 89.8 (21.2) | 69.6 (8.8) | 68.8 (15.9) | 81.9 (22.4) | |
| tPA†† | 36 (60) | 7 (64) | 2 (50) | 2 (50) | 25 (61) | |
| NIHSS at baseline† | 8.7 (5.8) | 7.2 (3.9) | 5.5 (1.3) | 4.3 (3.2) | 9.8 (6.4) | |
| Onset to Infusion Time† | 307.4 (50.0) | 320.4 (53.7) | 340.5 (18.4) | 305.8 (63.8) | 300.8 (49.4) | |
| 90 day mRS | 0 | 15 (25.0) | 2 (18.2) | 2 (50.0) | 2 (50.0) | 9 (22.0) |
| 1 | 15 (25.0) | 6 (54.6) | 1 (25.0) | 0 (0.0) | 8 (19.5) | |
| 2 | 9 (15.0) | 1 (9.1) | 0 (0.0) | 2 (50.0) | 8 (19.5) | |
| 3 | 11 (18.3) | 1 (9.1) | 1 (25.0) | 0 (0.0) | 7 (17.1) | |
| 4 | 2 (3.3) | 1 (9.1) | 0 (0.0) | 0 (0.0) | 1 (2.4) | |
| 5 | 3 (5.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 3 (7.3) | |
| 6 | 5 (8.3) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 5 (12.2) |
continuous variable, descriptive statistics are mean (sd)
categorical variable, descriptive statistics are n (%)
The only dose limiting toxicity occurred in an 88 year old man who had an NIHSS of 22 prior to enrollment and developed elevated hepatic enzymes one day prior to his death and after 3 doses of minocycline. There was no explanation for the elevated enzymes other than the minocycline and the impending death. The death was thought to be due to malignant cerebral edema but the elevation in hepatic enzymes was thought to be “possibly” due to the minocycline. The reversibility of the laboratory abnormality could not be determined due to the patient’s demise.
Table 2 gives the descriptive statistics for adverse events occurring within hospitalization overall and by dose tier. The most common types of adverse events that occurred during hospitalization were central nervous system (CNS) and cardiovascular events. CNS events included altered mental status, depression, fatigue, insomnia, labile emotions, light headedness, malignant brain edema, agitation, and insomnia. Cardiovascular related events included chest pain, heart palpitations, hypotension, bradycardia, tachycardia, and worsening hypertension. There were no recurrent strokes occurring within hospitalization. Other adverse events that were reported most frequently by patients included pain and edema. Gastrointestinal disturbances were reported in 12 patients and infection related adverse events within hospitalization were minimal (n=3 overall). Infusion related adverse events were uncommon with no phlebitis seen. Pulmonary adverse events included shortness of breath and chest pain, fluid overload, atelectasis (×2), small left pneumothorax, mild pulmonary edema, and bilateral pulmonary crackles.
Table 2.
In-Hospital Adverse Events Overall (N=132) and by Dose.
| AE Category | Specific AE | Overall (n=132) | 3mg/kg (n=23) | 4.5mg/kg (n=5) | 6mg/kg (n=5) | 10mg/kg (n=99) |
|---|---|---|---|---|---|---|
| Mortality | In-hospital | 3 (2.3) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 3 (3.0) |
| CNS | Dizziness | 3 (2.3) | 2 (8.7) | 0 (0.0) | 0 (0.0) | 1 (1.0) |
| Hemorrhagic Transformation+ | 3 (2.3) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 3 (3.0) | |
| Neuro-worsening++ | 5 (3.8) | 0 (0.0) | 1 (20.0) | 0 (0.0) | 4 (4.0) | |
| Other CNS | 8 (6.1) | 3 (13.0) | 0 (0.0) | 0 (0.0) | 5 (5.1) | |
| GI | Nausea/Vomiting /Diarrhea | 12 (9.1) | 3 (13.0) | 1 (20.0) | 0 (0.0) | 8 (8.1) |
| Skin | Skin Reactions | 4 (3.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 4 (4.0) |
| Phlebitis | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | |
| Infusion Reactions | 11 (8.3) | 7 (30.4) | 0 (0.0) | 0 (0.0) | 4 (4.0) | |
| Infections | UTI | 1 (0.8) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 1 (1.0) |
| Pneumonia | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | |
| Sepsis | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | |
| Fever | 2 (1.5) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 2 (2.0) | |
| Cardiovascular | MI | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| CHF | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | |
| Atrial Fibrillation | 3 (2.3) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 3 (3.0) | |
| Stroke or TIA | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | |
| Other CV Events | 16 (12.1) | 3 (13.0) | 1 (20.0) | 2 (40.0) | 10 (10.1) | |
| Renal Insufficiency* | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | |
| Thrombocytopenia** | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | |
| Elevated Liver Enzymes*** | 4 (3.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 4 (4.0) | |
| Reduced platelet count*** | 4 (3.0) | 0 (0.0) | 0 (0.0) | 1 (20.0) | 3 (3.0) | |
| Other Lab | 8 (6.1) | 0 (0.0) | 0 (0.0) | 1 (20.0) | 7 (7.0) | |
| Headache | 13 (9.8) | 2 (8.7) | 0 (0.0) | 1 (20.0) | 10 (10.1) | |
| Pulmonary | 8 (6.1) | 1 (4.3) | 0 (0.0) | 0 (0.0) | 7 (7.0) | |
| Other | 24 (18.2) | 2 (8.7) | 2 (40.0) | 0 (0.0) | 20 (20.0) |
CNS= central nervous system; UTI= urinary tract infection; MI= myocardial infarction; CHF= chronic heart failure; TIA= transient ischemic attack; CV= cardiovascular;
= as graded by investigator;
= greater than 4 point increase in NIHSS;
= serum creatinine > 2mcg/mL;
= platelets < 100,000;;
= from baseline
Pharmacokinetics
Pharmacokinetic parameters are summarized in Table 3. In Figure 1, the average concentration time curves for the 3 and 10 mg/kg doses are shown. In summary, the half life and peak concentrations were linear over the doses studied and the half life averaged near 24 hours.
Table 3.
Pharmacokinetics of Intravenous Minocycline by Dose
| Dose | Cmax (first) | Cmax(last) | Half-life (h) V(L) | V(L/kg) | AUC(24) | |
|---|---|---|---|---|---|---|
| 3.0mg/kg | 4.91(2.26) | 5.03(2.01) | 23.8(1.9) | 62.8(32.4) | 0.57(0.19) | 96.2(43.7) |
| 4.5mg/kg | 14.97(4.06) | 11.08(2.65) | 26.7(10.8) | 20.3(4.0) | 0.30(0.08) | 154.3(34.2) |
| 6.0mg/kg* | 14.32 | 17.21 | 21.6 | 28.9 | 0.34 | 223.3 |
| 10mg/kg | 17.93(7.99) | 23.65(10.24) | 26.9(6.2) | 44.1(20.7) | 0.57(0.24) | 347.7(113) |
= only one patient at 6 mg/kg enrolled in pharmacokinetic substudy
Figure.
Average minocycline serum concentrations over time in the 3 and 10 mg/kg dose group (n=12). Only patients with complete data out to 48 hours were included. Peak concentrations after the last dose declined in a log-linear manner with a half-life of approximately 24 hours.
Discussion
This is the first report of the safety and pharmacokinetics of escalating doses of intravenous minocycline in acute ischemic stroke patients. All of the 3 deaths occurring during hospitalization were attributed to the patient’s underlying illness and included 2 cases of malignant cerebral edema and one infarct extension. Despite the fact that 68% of the 60 subjects enrolled received the highest dose of 10 mg/kg, most adverse effects reported were mild, self-limiting and unrelated to dose. All were reversible and none were dose-limiting, except for the one case mentioned above where the patient succumbed to the effects of the stroke. It was reassuring that even at the highest dose, no cases of thrombophlebitis were reported. Mild to moderate burning at the infusion site was reported in twelve patients, but careful assessment did not reveal any inflammation or tissue destruction. Dizziness was not reported in any of the patients studied.
In this early phase dose-finding trial, the modified CRM failed to identify the maximum tolerated dose (MTC) of intravenous minocycline in acute ischemic stroke. The CRM was developed for use in the treatment of neoplastic diseases13, where the acute toxicities are particularly sinister and common. Minocycline, however, is an antibiotic with an admirable safety profile and decades of use in a wide range of patient populations.15,16 High dose intravenous minocycline has not been studied in humans and it was necessary to perform this investigation in order to demonstrate tolerability with concentrations in the serum that were shown to be robustly neuroprotective in animal models of stroke.2 In fact, the average peak concentrations were above13 mcg/mL at all doses studied beyond 3 mg/kg. Even in the 3 mg/kg dose, peak concentrations all but two patients exceeded that shown to be neuroprotective in rodents treated with 3 mg/kg of intravenous minocycline.2 There were two patients where the peak concentrations did not exceed 3 μg/mL, but both patients exceeded 100 kg in body weight and their actual mg/kg dose, given the capped dose at 270 mg, was much less than 3 mg/kg. The half-life of near 24 hours in the stroke population is similar to that previously reported in elderly patients,17 and will allow once daily dosing in future trials. Another pertinent pharmacokinetic finding in this study was the linearity of the parameters over the doses studied and the high variability in volume of distribution, consistent with the high mean and standard deviation of body weight in these patients. Despite the wide variation in peak concentrations, the admirable safety profile suggests a wide therapeutic index for this drug in stroke.
A recent trial of minocycline in Amyotrophic Lateral Sclerosis patients revealed a worse outcome in the group treated for 9 months, leading the authors to question the wisdom of continuing to pursue minocycline as a neuroprotective compound.18 In the case of acute neuroprotection, however, where dosing is limited to several days after the injury, we feel strongly that minocycline remains very promising. Even when the drug was administered orally for 5 days after acute ischemic stroke, significantly better stroke outcome was reported.19An oral dose would achieve serum concentrations similar to those of a 3 mg/kg intravenous dose in most patients, given that minocycline has 100% bioavailability and rapid absorption.20
Minocycline holds special promise as an adjunctive therapy to tissue plasminogen activator (tPA) in stroke. It has no negative effect on the fibrinolytic effect of tPA7 and reduces the incidence and impact of reperfusion hemorrhage in experimental models.7,8 More than 60% of our patients also received tPA and we had no cases of severe intracerebral hemorrhage (SITS-MOST21 or ECASS III22 criteria). The effects of minocycline on the inhibition of matrix metalloproteases (MMPs) may explain this perceived benefit. The vascular protective effect of minocycline in acute ischemic stroke deserves further study.
Intravenous minocycline, at doses between 4 and 10 mg/kg daily for three days, is safe and achieves concentrations in the serum that have been shown to be neuroprotective in experimental stroke. A large efficacy trial, with once daily dosing, should be conducted.
Acknowledgments
Acknowledgements and Funding
Funded by NIH – NINDS grant to DCH (R01 NS055728)
Minocin (for injection) was provided by Wyeth Japan
Special thanks to Triax Pharmaceuticals for access to Minocin regulatory files and Steven J. Projan, PhD. for assisting with drug acquisition.
DSMB-Bruce Coull M.D.; Brett Meyer M.D. Yuko Palesch PhD, Scott Janis PhD
Footnotes
Conflicts of Interest/ Disclosures
SCF: grant support/ consultant to Pfizer, Inc; consultant to Ferrer, grant support from VA Merit Review, NINDS (RO1 NS063965)
LCP: consultant for Genesis Biopharma; grant support from VA Merit Review
JAS: nothing to disclose
CEH: grant support: Actelion, NINDS; REACH co-founder
AE: grant support from VA Merit Review, AHA Established Investigator (EIA0740002N), NIH (RO1DK074385)
DCH: Speaker for Genentech, Boehringer Ingelheim; consultant for Ferrer; CoFounder REACH CALL, Inc
References
- 1.Arvin KL, Han BH, Du Y, Lin S, Paul SM, Holtzman DM. Minocycline markedly protects the neonatal brain against hypoxic-ischemic injury. Ann Neurol. 2002;52:54–61. doi: 10.1002/ana.10242. [DOI] [PubMed] [Google Scholar]
- 2.Xu L, Fagan SC, Waller JL, Edwards D, Borlongan CV, Zheng J, Hill WD, Feuerstein G, Hess DC. Low dose intravenous minocycline is neuroprotective after middle cerebral artery occlusion-reperfusion in rats. BMC Neurology. 2004 Apr 26;4:7. doi: 10.1186/1471-2377-4-7. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Chen M, Ona VO, Li M, Ferrante RJ, Fink KB, Zhu S, Bian J, Uo L, Farrel LA, Hersch SM, Hobbs W, Vonsattel JP, Cha JHj, Friedlander RM. Minocycline inhibits caspase 1 and caspase 3 expression and delays mortality in a transgenic mouse model of Huntington’s disease. Nat Med. 2000;6:797–801. doi: 10.1038/77528. [DOI] [PubMed] [Google Scholar]
- 4.Shan Z, Stavrovskaya I, Drozda M, Kim BYS, Ona V, Li M, Sarang S, Liu AS, Hartley DM, Wu DC, Gullans S, Ferrante RJ, Przedborski S, Kristal BS, Friedlander RM. Minocycline inhibits cytochrome c release and delays progression of amyotrophic lateral sclerosis in mice. Nature. 2002;417:74–78. doi: 10.1038/417074a. [DOI] [PubMed] [Google Scholar]
- 5.Yrjanheikki J, Tikka T, Keinanen R, Goldsteins G, Chan PH, Koistinaho J. A tetracycline derivative, minocycline, reduces inflammation and protects against focal cerebral ischemic with a wide therapeutic window. Proc Nat Acad Sci. 1999;96:13496–13500. doi: 10.1073/pnas.96.23.13496. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 6.Wang J, Wei Q, Wang C, Hill WD, Hess DC, Dong Z. Minocycline upregulates Bcl-2 and protects against cell death in mitochondria. J Biol Chem. 2004;279:19948–19954. doi: 10.1074/jbc.M313629200. [DOI] [PubMed] [Google Scholar]
- 7.Alano CC, Kauppinen TN, Vall AV, Swanson RA. MC inhibits poly (ADP ribose) polymerase I at nanomolar concentrations. Proc Natl Acad Sci. 2006 Jun 12; doi: 10.1073/pnas.0600554103. epub. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8.Brundula V, Rewcastle NB, Metz LM, Bernard CC, Yong VW. Targeting leukocyte MMPs and transmigration:minocycline as a potential therapy for multiple sclerosis. Brain. 2002;125:1297–1308. doi: 10.1093/brain/awf133. [DOI] [PubMed] [Google Scholar]
- 9.Machado LS, Sazanova I, Kozak A, Wiley DC, El-Remessy AB, Ergul A, Hess DC, Fagan SC. Minocycline and tissue plasminogen activator for stroke: Assessment of Interaction potential. Stroke. 2009;40:3028–3033. doi: 10.1161/STROKEAHA.109.556852. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 10.Murata Y, Rosell A, Scannevin RH, Rhodes KJ, Wang X, Lo EH. Extension of the thrombolytic window with minocycline in experimental stroke. Stroke. 2008;39:3372–3377. doi: 10.1161/STROKEAHA.108.514026. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 11.Fagan SC, Edwards DJ, Borlongan C, Xu L, Arora A, Feuerstein G, Hess DC. Optimal delivery of minocycline to the brain. Implication for human studies of acute neuroprotection. Exp Neurol. 2004;186:248–251. doi: 10.1016/j.expneurol.2003.12.006. [DOI] [PubMed] [Google Scholar]
- 12.Orti V, Audran M, Gibert P, Bougard G, Bressolle F. High-performance liquid chromatographic assay for minocycline in human plasma and parotid saliva. J Chromatogr. 2000;738:357–365. doi: 10.1016/s0378-4347(99)00547-2. [DOI] [PubMed] [Google Scholar]
- 13.O’Quigley JO, Pepe M, Fisher L. Continual Reassessment Method: A Practical Design for Phase I Clinical Trials IN Cancer. Biometrics. 1990;46:33–48. [PubMed] [Google Scholar]
- 14.Goodman SN, Zahurak ML, Piantadosi S. Some practical improvements in the continual reassessment method for phase I trial designs. Stat Med. 1995;14:1149–61. doi: 10.1002/sim.4780141102. [DOI] [PubMed] [Google Scholar]
- 15.Clark BJ, Hodgson CR, Dornbush AC, Hutchinson J. Minocycline administered intravenously: pharmacological activity and clinical experience. Curr Ther Res. 1974;16:865–877. [PubMed] [Google Scholar]
- 16.Tilley BC, Alarcon GS, Heyse SP, Trentham DE, Neuner R, Kaplan DA, Clegg DO, Liesen JCC, Buckley L, Cooper SM, Duncan H, Pillemer SR, Tuttleman M, Fowler SE for the MIRA Trial Group. Minocycline in Rheumatoid Arthritis. A 48-week, double-blind, placebo-controlled trial. Ann Int Med. 1995;122:81–89. doi: 10.7326/0003-4819-122-2-199501150-00001. [DOI] [PubMed] [Google Scholar]
- 17.Yamamoto T, Takano K, Matsuyama N, Koike Y, Minshita S, Sanaka M, Kuyama, Yamakana M. Pharmacokinetic characteristics of minocycline in debilitated elderly patients. Am J Ther. 1999;6:157–160. doi: 10.1097/00045391-199905000-00006. [DOI] [PubMed] [Google Scholar]
- 18.Gordon PH, Moore DH, Miller RG, Florence JM, Verheijde JL, Doorish C, Hilton JH, Spitalny GM, MacArthur RB, Mitsumoto H, Neville HE, Boylan K, Mozaffar T, Belsh JM, Ravits J, Bedlack RS, Graves MC, McCluskey LF, Barohn RJ, Tandan R for the Western ALS Study Group. Efficacy of minocycline in patients with amyotrophic lateral sclerosis: a phase III randomized trial. Lancet Neurology. 2007;6:1045–1053. doi: 10.1016/S1474-4422(07)70270-3. [DOI] [PubMed] [Google Scholar]
- 19.Lampl Y, Boaz M, Gilad R, Lorberboym M, Dabby R, Rapoport A, Anca-Hershkowitz M, Sadeh M. Minocycline treatment in acute stroke. Neurology. 2007;69:1404–1410. doi: 10.1212/01.wnl.0000277487.04281.db. [DOI] [PubMed] [Google Scholar]
- 20.Welling PG, Shaw WR, Uman SJ, Tse FLS, Craig WA. Pharmacokinetics of minocycline in renal failure. Antimicrob Agents Chemother. 1975;8:532–537. doi: 10.1128/aac.8.5.532. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 21.Wahlgren N, Ahmed N, Davalos A, Ford GA, Grond M, Hacke W, Hennerici MG, Kaste M, Kuelkens S, Larrue V, Lees KR, Raine RO, Soinne L, Toni D, Vanhooren G for the SITS-MOST Investigators. Thrombolysis with alteplase for acute ischaemic stroke in the Safe Implementation of Thrombolysis in Stroke – Monitoring Study (SITS-MOST): an observational study. Lancet. 2007;369:275–282. doi: 10.1016/S0140-6736(07)60149-4. [DOI] [PubMed] [Google Scholar]
- 22.Hacke W, Kaste M, Bluhmki E, Brozman M, Davalos A, Guidetti D, Larrue V, Lees KR, Medeghri Z, Machnig T, Schneider D, von Kummer R, Wahlgren N, Toni D for the ECASS Investigators. Thrombolysis with alteplase 3 to 4. 5 hours after acute ischemic stroke. N Engl J Med. 2008;359:1317–1329. doi: 10.1056/NEJMoa0804656. [DOI] [PubMed] [Google Scholar]