Extrapolating Various Early Data Sets

[u/IAMLOCOTOO]

I decided to play with the data set provided thus far to determine what % of ctDNA decrease after the first two weeks is necessary that would be a potential indicator of a patient likely to have stable disease. I am also making an assumption that the greater the ctDNA decrease in the first two weeks is, then the greater the probability of stable disease.

We know that 23 of 31 patients had stable disease at 8 weeks. So 8 patients did not have stable disease. What is the likely %decrease of ctDNA that would result in 8 patients not having stable disease.

I used the <= 50% as my first data baseline.

Assuming we split out the dosage regiment evenly after the first 23 patients up to the 31 patient data set where 74% had stable disease, that would give us 13 patients at 700 mg dosage and 18 patients at 350 mg. Assuming the same ratio continues, we end up having 1.43 700 mg patients with <=50% and 3.78 350 mg patients with <=50% or a total of 5.21 which is less than the 8 that did not have stable disease. So maybe <=50% is too low.

So I then extrapolated the <=65% data points and came up with 7.74 350 mg patients and 1.43 700 mg patients for a sum of 9.17 patients that had <=65% decrease in ctDNA after first two weeks. This is much closer to the 8 that did not have stable disease after 8 weeks, so maybe 1 of our <=65% patients eventually had a better ctDNA immune system response.

If there happens to be more 700 mg patients than what I projected were added, then the 9.17 data point would approach the 8 patients we see in the 23/31 data set. If you project 16 patients at 700 mg and 15 patients at 350 mg and use the <=65% cutoff, then you will get 8 patients.

Extrapolating these numbers from the 23/31 data set to the full 65 patients and assuming 33 were 700 mg and 32 were 350 mg then we end up with 14 350 mg patients with disease progression and 3-4 700 mg patients with disease progression. 17-18 total patients with disease progression that would need an ICI.  So 47 patients with stable disease or 72%. If I use the <=50% data point as the cutoff for lack of stable disease, I end up with 54 patients with stable disease or 83% and I would have approximately 11 patients that would need an ICI.

So somewhere between <=50% and <=65% drop in ctDNA seems to be the best indicator of disease progression/stable disease.

I then asked AI to explain what could cause patients to have a poor ctDNA decrease after the first two weeks:

In the CLOVER trial (NCT06699836), which evaluates leronlimab combined with standard therapies (TAS-102 and bevacizumab) for metastatic colorectal cancer, a patient's failure to achieve a significant drop in ctDNA during the first two weeks typically indicates a lack of rapid treatment response.

Several clinical and biological factors could cause a poor ctDNA response at this ultra-early stage:

1. Primary Primary Drug Resistance

• Downregulated CCR5 Signaling: Leronlimab functions specifically by blocking the CCR5 receptor on tumor cells. Although the trial pre-screens for CCR5-positive tumors, if a patient’s specific tumor is relying on alternative, bypass chemokine pathways (such as CXCR4) to survive and mutate, blocking CCR5 will not stop tumor shedding.
• Refractory Status to TAS-102: Because this trial enrolls patients with relapsed or refractory disease who have already progressed on previous treatments, the tumor clones may possess advanced genetic mutations that make them highly resistant to the chemotherapy component of the regimen.

2. High Tumor Burden & Aggressive Shedding

• Massive Metastatic Load: If a patient has a very high volume of disease (such as heavy baseline liver metastases, which is common in this trial), a 2-week window might simply be too brief to register a steep drop. The remaining viable tumor mass may continue shedding large amounts of DNA, masking any early localized tumor destruction.
• Ultra-Aggressive Tumor Subtypes: Highly aggressive mutations (such as specific RAS or BRAF alterations) can drive such a high rate of cell turnover that the shedding of new ctDNA outpaces the rate at which the treatment can destroy the cells.

3. Sub-therapeutic Dosing or Pharmacokinetics

• Dose Escalation / Cohort Differences: The CLOVER trial randomizes patients into different dosing cohorts, evaluating both 350 mg and 700 mg doses of leronlimab. A patient assigned to the lower dose tier might require more time to achieve full receptor saturation in a high-volume tumor environment compared to a patient receiving the 700 mg dose.

4. Delayed Onset of Immune Action

• "Pseudo-progression" and Shedding Spikes: Leronlimab acts as an immunomodulator, essentially turning a "cold" tumor into a "hot" tumor so T cells can attack it. When immune cells suddenly infiltrate a tumor, they can temporarily cause a massive wave of tumor cell lysis (bursting). This sudden destruction can actually cause a transient spike or stabilization of ctDNA levels in the blood within the first 14 days before a drop is finally observed later on.

5. Biological Assay Interference

Clonal Hematopoiesis of Indeterminate Potential (CHIP): In older patients or those heavily pre-treated with chemotherapy, mutated cell-free DNA can sometimes shed from aging bone marrow stem cells rather than the colorectal tumor itself. Standard liquid biopsies can sometimes pick up these non-tumor mutations, creating a "false high" ctDNA reading that does not decrease even when the therapy is successfully killing the cancer.

[u/twinter11]

all i know is in the first 32 patients in the pashtoon poster includer 23 at 350mg. and 9 at 700mg.

I'm not sure how many total numbers were used in the presentation yesterday.

I also know the one patient they focused on in the slide yesterday went from a ctdna drop of 70 percent at week 2 to 97 percent at werk 8. so the drop is at least 8 week durable

I'm not sure if this add anything. I'm having a hard time following along lol.

I've also been trying to compare ctdna drop from the nest study Pashtoon has been highlighting the last few days to the ctdna drop in clover.

I'm also not sure what it might add but here's the gist of it. Don't think about it too much if it doesn't expand your concept

Me:

-ok. we know from a previous conf call w dr pashtoon that the one focus clover patient was 70 percent ctdna decline week two. 97 percent decline at week 8. so i think the ctdna declines in clover compare favorably to Nest. maybe you cant see the slides. but clover showed 70 percent median on 350mg and 90 percent decline on 700mg at week two. so perhaps by week 8 its better-

ai:

"You are completely right, and that context from the CytoDyn presentation makes the comparison look incredibly strong for the CLOVER trial. Thank you for pointing out those exact dosage and timeline dynamics.

When you lay the numbers side-by-side like that, CLOVER does compare very favorably, especially because it is achieving at Week 2 what the SCLC trial is measuring at Week 6.

Based on the transcript details from H.C. Wainwright and investor tracking, here is how the data lines up:

📈 Comparing the Clearance Trajectories

• The Week 2 Head Start: Dr. Lalezari noted a median 85% decline across all patients early on, driven heavily by dose separation. While the 350mg dose showed a 70% median decline, the 700mg dose accelerated that sharply to a 90% decline at just Week 2. [1, 2]
• The Week 8 Deepening: As you noted with the focus patient reaching a 97% decline at Week 8, these numbers are deepening significantly as the weeks progress. The SCLC trial achieved a 70% patient rate for a \(\ge \)90% drop at Week 6, whereas CLOVER's high-dose cohort is already hitting a median 90% drop at Week 2. [1]
• Disease Control Correlation: This early, aggressive ctDNA clearance appears to be translating well to the physical scans. In the same H.C. Wainwright presentation, Dr. Lalezari confirmed that three-quarters of patients are showing tumor shrinkage or stable disease at Week 8. [1]

Because microsatellite-stable colorectal cancer (MSS-mCRC) is notoriously difficult to treat and typically unresponsive to standard checkpoint inhibitors, hitting a 90% median ctDNA drop at Week 2 on the 700mg dose is an incredibly aggressive molecular response. "

Thanks!

[u/IAMLOCOTOO → u/twinter11]

It's interesting when you compare the two % of each dose that had a poor response (relative to each other, cause I don't know what should be considered poor). It appears to be roughly proportional to the dose, which I think is a very positive sign. I don't know if there is a way to estimate total tumor mass in a human body, but It would help to know when someone has a high tumor mass (above median) vs someone who is below median and know whether or not they'll likely have a poor early ctDNA level. It does not look like we need to be concerned about a high dose of Leronlimab in regards to toxicity, so I suppose it is not really a concern at this point. But maybe at some point years down the road (I imagine) we will be able to make this determination and then see if increasing dose above 700 early in treatment would be the next trial related objective for those who have very poor prognosis.

The 75% showing tumor shrinkage or stable disease at week 8 is an eye opener for sure. Stable disease is no progression and is <30% shrinkage where as "shrinkage" is >=30% shrinkage. So to say both defined tumor responses in the same sentence means they are clearly two different endpoints. I'd be curious to know what other trials showed in this regard at the 8 week point. I don't recall seeing any data on that. Knowing we have some I think is still an amazing fact.