G100 and pembrolizumab: a phase 1/2 trial testing newer drugs for people with follicular lymphoma and marginal zone lymphoma

This trial is now closed. It is no longer recruiting participants.

Preliminary results from this trial were presented at a major conference in December 2017.

Purpose of trial

The aims of the trial are:

  • to find out how effective G100 is on its own and combined with pembrolizumab
  • to find out the possible side effects of these treatments
  • to look at the immune system response to treatment.


G100 and pembrolizumab are newer drugs that affect how your immune system works. They harness the power of your own immune system and allow it to recognise and kill the lymphoma cells.

There are three parts to this trial. People with marginal zone lymphoma (MALT lymphoma, nodal marginal zone lymphoma, splenic marginal zone lymphoma) can enter part 1 only. People with follicular lymphoma can enter part 1, part 2 or part 3. You can only enter this study if your doctor is planning to treat you with radiotherapy to your tumour. Everyone in this trial receives radiotherapy before the test drugs.

Different doses of G100 are being tested in this trial:

  • Part 1 is to find the best dose of G100. Participants have 1 of 2 doses of G100. This is done by dose escalation. Participants are treated in groups of 3. The first 3 participants have the lowest dose. If this doesn’t cause serious side effects, the next 3 participants have the higher dose. The highest safe dose is tested in part 2.
  • Part 2 is to test how well the best dose of G100 from part 1 works on its own or in combination with pembrolizumab. An additional higher dose of G100 may be tested in people with tumours of 4 cm or greater if there are no safety concerns from part 1 of the trial.
  • Part 3 is to test the best dose of G100 in a larger group of participants.

Participants in parts 1 and 3 have radiotherapy and G100. In Part 2, participants have radiotherapy and are randomised to receive G100 or G100 with pembrolizumab. You can’t choose which treatment you have and neither can your doctor. You are told which treatment you are having and given information about it.

G100 is given by intratumoural injection (injection into the tumour). Pembrolizumab is given intravenously (through a drip into a vein).

In the trial, you have radiotherapy on day 1 only.

You have an injection of G100 on day 2. You then have G100 once a week for a total of 6 treatments. If there is still some tumour left after 6 treatments, you may be able to have a further 3 injections of G100.

If you are also having pembrolizumab, you have radiotherapy and G100 as described above. You also have pembrolizumab on day 14 (2 weeks after the radiotherapy) then once every 3 weeks. You can continue to have pembrolizumab for up to 2 years as long as it is helping to control your lymphoma and you are not having troublesome side effects.

Who can enter

Your consultant can give you advice on whether this trial might be suitable for you.

Around 40 people are needed for this trial.

You may be able to enter if:

  • You have an untreated, relapsed or refractory follicular lymphoma or marginal zone lymphoma.
  • Your doctor is recommending radiotherapy to your tumour.
  • You have lymphoma in at least 1 place that’s outside the area targeted by radiotherapy.
  • You have a tumour that can be treated by injection into the tumour.
  • You are well enough to look after yourself and are up and about and able to carry out light work (eg light housework, office work) daily.
  • Your ECG (heart trace) test results are acceptable.
  • You and your partner are willing to use reliable contraception during treatment and for at least 4 months after treatment if there is any chance of you or your partner becoming pregnant.
  • Your blood and other health test results are satisfactory.
  • You are 18 or over.

You will not be able to enter if:

  • Your lymphoma is in your central nervous system (CNS; brain and spinal cord).
  • You’ve had another anti-cancer treatment in the 4 weeks before starting the trial treatment.
  • You’ve had another experimental drug in the last 4 weeks.
  • You’ve been treated with a similar drug before.
  • You have any health problems that might make it unsafe for you to have the trial treatment.
  • You still have significant side effects from your previous treatment.
  • Your immune system is low because of steroid treatment given in the last 4 weeks or because of other immuno-suppressive drugs.
  • You have significant heart problems or have had a heart attack in the last 6 months.
  • You’ve had another cancer in the last 2 years, except certain localised cancers.
  • You have HIV, Hepatitis B virus, Hepatitis C virus or active tuberculosis or you’ve had a serious infection in the last week.
  • You have a significant autoimmune condition (where your body attacks itself) – ask your doctor if this applies to you.
  • Any of the study drugs are not suitable for you, eg because of allergies to any the ingredients.
  • You are taking anti-coagulant (blood thinning) drugs or are at risk of significant bleeding.
  • You won’t be able to enter part 2 of the trial if:
    • You have interstitial lung disease (scarring or inflammation of your lungs).
    • You’ve had a live vaccine in the last 30 days.
    • You’ve had an allogeneic (donor) stem cell transplant in the last 5 years.

Further information

More information about this trial is available at clinicaltrials.gov.