If you are not diagnosed with the disease, but have suffered from unusual, painful sensations in your limbs, you may be eligible.
Small fiber neuropathy (SFN) is a disorder that only affects the small sensory nerves leading to chronic pain and altered sensations of pain in the distal limbs. This type of disorder is normally characterized by severe pain, which begins in the feet or hands.
The symptoms of this disorder are characterized by unusual sensations of pain or perception such as:
- Pins and needles
- Burning pain
- Electric shock-like brief sensations of pain
A diagnosis of SFN is based on medical history, a clinical examination, and laboratory results. The most common causes of SFN are diabetes and impaired glucose tolerance. However, SFN can occur due to unknown reasons, and is defined as idiopathic SFN.
Currently, the treatment of SFN depends on the underlying cause, e.g. diabetes. If the SFN is caused by pre-diabetes or diabetes, the aim is to get the impaired glucose tolerance or insulin resistance under control. If the diabetic interventions singularly cannot remove the pain sensations or the reason for the SFN is unknown (idiopathic), current treatment for the painful sensory sensations and perceptions can be treated with e.g.:
- Anti-seizure medication
- Painkillers (including opioids)
- Referral to pain clinics for multidisciplinary approach to pain management
However, there are no current treatments indicated specifically for this type of pain and the abovementioned treatment options can have limited effect in relation to the specific type of SFN pain, which is the reasoning for the research into new types of treatment for SFN.
Pain medication, including opioids, are commonly used to treat the pains associated with SFN, however, the limited efficacy and poor tolerability of painkillers signals a need for more effective therapies for SFN patients.
If you are interested and qualify to participate in a study, you may receive placebo instead of the investigational medication. A placebo is a substance that resembles the investigational medication but contains no active ingredients. The use of placebo is standard practice in clinical studies investigating the effect of investigational medications and is used as a measure of comparison. Your chance of receiving placebo will be explained by study staff in advance of your participation. Please notice, participating in a clinical study and receiving placebo is greatly contributing to the clinical research. However, should you end up receiving placebo, you are permitted to use rescue medication within dosing limits, and you can always discontinue your participation if you do not achieve pain relief and resume your standard-of-care therapy.
Who can participate?
- Male and females
- Above 18 years old
There will be no additional costs to you if you choose to participate in a clinical study. The investigational medication and any tests required by the study are provided by the researchers, and you will receive reimbursement for travel expenses incurred by taking part in the study until your participation is complete.
Please note that taxes may need to be paid on travel expense reimbursement; it might also need to be reported to authorities.
Clinical research studies assess the safety and effectiveness of investigational medications in reducing the pain associated with SFN. If you are interested and qualify to participate, staff at the study site will provide you with a detailed overview of the steps required to participate before you agree to take part. The staff will also take the time to review and discuss any questions you may have to ensure you are comfortable with participation.
The following are examples that are typical of participating in a pain related clinical research study.
At the beginning of participation an eDiary may be provided to you, in which you must keep track of your condition throughout your participation. This helps study staff monitor your pain and participation. Many pain studies also require completion of various study periods in advance of receiving the investigational medication. This is done to ensure that your participation is valid.
Visits to the nearest clinic are very important to perform different clinical assessments, which must be performed at specific time points during the study. Examples of different periods of pain related studies are described below. The duration of the periods will vary by clinical research study and will be explained in detail by study staff if you pre-qualify and are interested in learning more about participation.
A screening assessment period
A period, which is conducted to confirm your eligibility into the research project based on clinical or laboratory assessments. During this period, you will visit the nearest clinical site and may need to supply them with a single skin tissue sample for analysis.
A taper period
If you are currently using medications for pain, you may need to enter a taper period in order for you to decrease and end your current use of painkillers.
A washout period
As soon as you discontinue your current pain medications, you may enter a washout period. This is to ensure that no other medications within your body interfere with the effect of an investigational medication. Therefore, no medications for pain will be allowed during this period.
A run-in period
In this period, all enrolled subjects typically receive the investigational medication to ensure all study participants respond to the investigational medication.
All enrolled study participants who responded to the investigational medication during the run-in period, will be randomly assigned to receive doses of the investigational medication or placebo. Neither you nor the clinical personnel will know what treatment you are receiving.
Your health will be closely monitored by study staff throughout your participation a clinical research study. You can withdraw your participation at any time.