Safety and efficacy of cell therapies administered in the acute and subacute stages after stroke: a meta-analysis

Are patient educational resources effective at deterring stroke survivors from considering experimental stem cell treatments? A randomized controlled trial

OBJECTIVE

To evaluate whether online resources developed to educate people about the risks associated with experimental stem cell (SC) treatments influence stroke survivors' attitudes about the safety and effectiveness of these treatments.

METHODS

Adult stroke survivors who had not previously received SC treatments (N = 112) were recruited from international stroke advocacy/support groups for a prospective, parallel-group randomized controlled trial. Participants indicated whether they were considering SC treatments (yes/no) prior to, immediately following, and 30-days after reading/viewing the International Society for Stem Cell Research booklet or Stem Cell Network video. Participant attitudes regarding the safety, effectiveness, accessibility and affordability of SC treatments were examined on each occasion, and compared to those of a waitlist control group.

RESULTS

Significantly fewer participants were considering SC treatments immediately after reading the SC research booklet (p =.031), although neither intervention had any impact after 30-days (p >.05). Waitlist and intervention groups reported positive attitudes toward SC treatments at each assessment.

CONCLUSIONS

Stroke survivor attitudes toward SC treatments were initially influenced by the patient booklet, however these changes were not maintained.

PRACTICAL IMPLICATIONS

Clinicians are encouraged to initiate discussions about experimental SC treatments during inpatient rehabilitation and to reinforce the risks throughout subsequent care.

Cell-Based Therapies for Stroke: Are We There Yet?

Stroke is the second leading cause of death and physical disability, with a global lifetime incidence rate of 1 in 6. Currently, the only FDA approved treatment for ischemic stroke is the administration of tissue plasminogen activator (tPA). Stem cell clinical trials for stroke have been underway for close to two decades, with data suggesting that cell therapies are safe, feasible, and potentially efficacious. However, clinical trials for stroke account for <1% of all stem cell trials. Nevertheless, the resources devoted to clinical research to identify new treatments for stroke is still significant (53–64 million US$, Phase 1–4). Notably, a quarter of cell therapy clinical trials for stroke have been withdrawn (15.2%) or terminated (6.8%) to date. This review discusses the bottlenecks in delivering a successful cell therapy for stroke, and the cost-to-benefit ratio necessary to justify these expensive trials. Further, this review will critically assess the currently available data from completed stroke trials, the importance of standardization in outcome reporting, and the role of industry-led research in the development of cell therapies for stroke.

Stroke survivor attitudes toward, and motivations for, considering experimental stem cell treatments

Purpose: Interest in stem cell treatments is increasing among some patient groups, but it is unclear whether this holds true for stroke survivors. This study examined stroke survivor attitudes toward stem cell treatments and identified a number of variables that may increase the likelihood that patients will consider these treatments.Methods: Adult stroke survivors (N = 183) were recruited (stroke advocacy/support groups, outpatient register) for a cross-sectional study. Attitudes to stem cell treatments were surveyed, guided by the Theory of Planned Behavior. Demographic information was collected, and a number of self-report medical, cognitive and psychological measures completed.Results: Twenty-five percent (n = 46) of respondents indicated they were considering undergoing stem cell treatments, although most were unsure about the safety/effectiveness and accessibility/affordability. Stroke survivors with positive attitudes toward stem cell treatments, longer post-stroke intervals, poorer physical functioning, younger age, and greater perceived caregiver burden were more likely to be considered experimental treatments (odds ratios = 1.22, 1.08, 0.95, 0.96, 1.07; respectively).Conclusions: Stroke survivors may consider undergoing experimental stem cell treatments despite uncertainty regarding the risks/benefits. Clinicians should be mindful of the factors that may increase the likelihood of patients considering these treatments and intervene, where appropriate, to clarify any misconceptions regarding the medical/financial risks.IMPLICATION FOR REHABILITATIONStem cell treatments offer a new focus for reducing stroke-related disability, although their safety and effectiveness have yet to be established.Despite uncertainty regarding the medical risks and benefits associated with stem cell injections, stroke survivors may still consider undergoing treatment in private, unregulated clinics.A number of factors, including younger age, longer post-stroke interval, poorer physical functioning, and perceived caregiver burden may place stroke survivors at an increased risk of considering these treatments.Clinicians should endeavor to educate stroke survivors regarding the risks and benefits of these experimental treatments and clarify any misconceptions, in order to reduce the likelihood that they will consider these as-yet unproven treatments.

Safety and effectiveness of stem cell therapies in early-phase clinical trials in stroke: a systematic review and meta-analysis

Stem cells have demonstrated encouraging potential as reparative therapy for patients suffering from post-stroke disability. Reperfusion interventions in the acute phase of stroke have shown significant benefit but are limited by a narrow window of opportunity in which they are beneficial. Thereafter, rehabilitation is the only intervention available. The current review summarises the current evidence for use of stem cell therapies in stroke from early-phase clinical trials. The safety and feasibility of administering different types of stem cell therapies in stroke seem to be reasonably proven. However, the effectiveness needs still to be established through bigger clinical trials with more pragmatic clinical trial designs that address the challenges raised by the heterogeneous nature of stroke per se, as well those due to unique characteristics of stem cells as therapeutic agents.

Cell therapies administered in the chronic phase after stroke: a meta-analysis examining safety and efficacy

Aim: To assess the safety and efficacy of cell therapies for chronic stroke. Methodology: Five databases were searched for treatments administered >90 days post-stroke. Reporting quality, adherence to research guidelines, treatment safety (risk ratios/pooled incidence rates) and neurological/functional efficacy (Hedge’s g) were all evaluated. Results: Twenty-three studies examined 17 treatments. Reporting quality scores were medium to high, but adherence to recommended guidelines was lower. Three treatments resulted in serious adverse events; four improved outcomes more than standard care. However, many studies were under-powered and individual patients varied in their response to some treatments. Conclusion: Preliminary findings suggest that some cell therapies may be relatively safe and effective, but larger double-blinded placebo-controlled studies are needed to establish the long-term risks and benefits.