Soligenix Inc. has just announced that they’ve received a Pediatric Investigation Plan waiver, or PIP waiver from the MHRA, the UK’s marketing agency. Now, Soligenix Inc has a pediatric waiver from both the EU and the UK. This PIP waiver will allow them to work toward marketing authorization for their novel therapy called HyBryte, a treatment for cutaneous T-cell lymphoma (CTCL) without a pediatric trial.
HyBryte has already been studied in a very successful Phase 3 trial for early stage CTCL. The new PIP waiver for all pediatric subsets was granted because its not feasible to conduct a pediatric clinical trial in this rare disease.
CTCL
CTCL is a form of non-Hodgkin’s lymphoma (NHL). NHL is a cancer which affects the white blood cells. CTCL specifically is caused by the expansion of malignant T-cell lymphocytes. Other NHLs typically are caused by the expansion of B-cell lymphocytes. That’s what makes CTCL so unique. The malignant cells in CTCL migrate to the skin, forming lesions which may progress to tumors. These can regress with treatment, but they typically return in the same place on the body.
Median survival ranges from 12 years to 2.5 years, depending on the stage of the disease and unfortunately, there is currently no cure.
HyBryte
HyBryte is a photodynamic therapy which uses visible light (which is not carcinogenic) to activate its mechanism. The therapy’s active ingredient is called synthetic hypericin, a photosensitizer. HyBryte is put on skin lesions, absorbed by the T-cells, and then activated with visible light 16-24 hours later. Since visible light is used, it is able to penetrate deep into the patient’s skin, treating disease that has progressed through many skin layers.
This therapy has already been given Orphan Drug Designation from the EMA and FDA and Fast Track Designation from the FDA.
A Phase 2 trial was able to show a statistically significant improvement in CTCL patients when HyBryte was used.
The Phase 3 trial called FLASH included 169 patients with various stages of CTCL. All patients went through 3 treatment cycles. For 6 weeks, patients were given treatment twice a week. Response was evaluated on the 8th week at the end of each of the 3 cycles.
Cycles
In the first cycle, 116 patients were given the treatment, and 50 were given a placebo. 16% of those in the treatment group achieved a minimum of 50% reduction in their skin lesions. For the patients in the placebo group, just 4% achieved this. The treatment was also found to be well tolerated across patients.
In the second cycle, 110 patients received the treatment for 12 weeks, and 45 received the placebo for the first 6 weeks before they were switched to the treatment. For those who were given the treatment for the entire 12 weeks, the response rate was 40%. The significant improvement for the 12-week group also demonstrated that longer treatment leads to better outcomes. Further, the treatment was found to be able to treat plaque lesions which are notoriously hard to treat.
In the third cycle, safety was the focus. Treatment was solely elective, and 66% of all patients opted to continue. Among the patients who participated in all 3 cycles, 49% had a treatment response.
Throughout all cycles, the treatment was found to be well-tolerated and safe.
Safety
One reason why researchers are so hopeful about this new therapy is that it has demonstrated incredible safety throughout every trial.
The mechanism of action of HyBryte does not damage the DNA like many current treatments do as they rely on ultraviolet light. Every current therapy has serious side effects such as melanoma, skin aging, and skin damage. Some of these side effects can be fatal. In fact, they are so likely to be more harmful than helpful that they are only approved when other treatments fail or there isn’t a front-line therapy accessible.
Since HyBryte is not absorbed systemically, and it uses a light source which is not a carcinogenic, researchers are hopeful it could provide the safest option yet for CTCL patients.
You can read more about this novel therapy here.
