Hi Salty
In the Clinical Trial update of 10 August last year the "anticipated" study completion date was April 2021. Allowing a month or two for collation of the data and a report would have been expected around June this year.
However the next Clinical Trial update, on 20 May this year, gives an anticipated study completion date of February next year. https://clinicaltrials.gov/ct2/history/NCT02795988?V_19=View#StudyPageTop A recent video presentation by Leslie Chong also showed expected completion in Q1 next year.
The study completion date has blown out because the study is designed to show Overall Survival data (OS), which is the length of time that patients survive whilst on the treatment. ie. The Study "Primary Outcome measure" is: "Clinical efficacy of IMU-131 (Phase 2)To evaluate the clinical efficacy of IMU-131 based on overall survival (OS)."
So.... if the patients live longer than expected then the trial end date has to be pushed back because there is no final data on Overall Survival - but that is of course good news for the patients, and good news for the company too, because it indicates that the treatment is having a beneficial effect. Note: the patients selected for the study are all regarded as terminal. To get in to the study the patients had to have metastatic or advanced gastric cancer which is inoperable. These are very unwell people.
Some of the commentary here on HC is confused however, because posters are sometimes unclear in what they mean by "results." As mentioned above, the primary study outcome is "overall Survival," but the Phase 2 study will also be collecting data on 8 "Secondary Outcomes" and 2 "Exploratory Outcomes." That makes a total of 11 "results" which will be included in the final study report.
There is no obligation on the company to collect and report interim data ahead of study completion but they did provide an interim data report on one of the "Secondary Outcomes" - Progression Free Survival (PFS). That interim report was Announced on 23 November last year.
The interim PFS data was very positive and it helped give the share price a good boost. Based on the interim PFS data the Independent Data Monitoring Committee even recommended that they reduce the total number of planned patient enrolments, because in their view the study had already proven that Her-vaxx was having a beneficial effect: "The Independent Data Monitoring Committee (IDMC) confirms a favourable survival outcome with no added toxicity for HER-Vaxx combined with SOC chemotherapy over chemotherapy alone and advises to lower the number of patients required for study completion. " Source: https://hotcopper.com.au/threads/ann-imugene-her-vaxx-shows-positive-overall-survival-in-trial.5770964/.
Then on 21 April the company announced that they had reached the secondary endpoint of Progression Free Survival data. ie. the study could now generate final data on PFS.
Back then they were planning to finalise that PFS data and get it to the Independent Data Monitoring Committee. From memory Leslie stated in an interview that the report of the PFS data might be ready as early as this month. Many here on HC - myself included - have been quite excited at the prospect of seeing the final PFS data and we have been looking forward to seeing it very soon.
However, in LC's recent NWR Virtual Investor conference video (available on Youtube), from around 24:47 onwards LC is asked a question about the Her-vaxx data and she replies that the "prudent thing" is to release the PFS and OS data together, instead of separately. She states that they need 24 of the 36 patients to reach the OS point (sadly - end of life), and she states that "... we are just at a few more patients before we reach the number 24..."
So based on those comments it's looks like we won't be seeing the final PFS data until the study is completed, so we will be waiting till Q1 next year.
That delay has generated a bit of heat from some posters here on HC who were - like me - looking forward to seeing the PFS data very soon. Some of them regard it as an indication that the final PFS data may be less good than the interim data released in November. I'm not of that opinion myself, but I am by nature more patient than some of my fellow shareholders.
It's worth re-reading the Announcement of 21 April. In that Announcement the key statement is:
"Following completion of recruitment in January 2021, the important clinical endpoint of Progression Free Survival (PFS) has been met after the statistically significant required number of PFS events has occurred. Data from these 24 events will now be analysed with the final PFS read- out expected within months."
What they are saying here is that to provide a "statistically significant" report on PFS they need 24 patients to reach a PFS "event." (ie their disease starts to progress again). The Ann is telling us that as of 21 April they did indeed finally (and sadly for those patients) have 24 disease progression "events" and they were planning to crunch the data and provide a "final PFS readout" very soon.
Now the CEO is saying that it would be more "prudent" to release the PFS data when the OS data is available - ie at the end of the study.
Interpretation 1:
( @fourdollars posted on this recently) - possibly this means that they have looked at the latest PFS data and it doesn't look as good as the interim PFS data, so they are sitting on it instead of releasing it.
Interpretation 2:
(My own view) - On 21 April they only had disease progression for 24 out of the 36 patients enrolled.. That was enough to provide a "statistically significant" report but it also meant that one third of the patients had still not reached disease progression. ie. their cancer was either still stable or improving. (note: we don't know which trial arm they were on - Her-Vaxx plus Chemo, or just Chemo). So although the Announcement used the term "final PFS readout" - it would still only be an interim report.
Now there is a related issue here. Quite a few posters on HC have said words to the effect of: "Well if the patients are slower to die than expected, and the study completion date is pushed out by that, how will they ever end the study? What if some of the patients survive indefinitely? Will we have to wait for all the patients to die before they can end the study??"
Leslie's comment in the NWR irtual Investor conference video gives us the answer. She states that they need 24 of the 36 patients to reach the OS point, (end of life), and she states that "... we are just at a few more patients before we reach the number 24..."
So - just the same as with PFS - they only need 24 deaths out of 36 to give a statistically significant result, and (sadly) they are getting close to that point. When they do reach 24 deaths they can then provide a report on OS, but if that takes till the end of this year (for example), then that also gives them another 8 months of data on PFS (compared to a 21 April readout) which will make the PFS data even more reliable - so why not hold off on the PFS data till then?
That is my interpretation of what LC means when she says it would be the "prudent thing" to release PFS and OS data together.
So.....
Not a short answer, @salty74 - but I hope it helps.
Cheers
Dave 
(20min delay)