AC Immune SA (ACIU) Stock Analysis & Price (Updated Oct 16, 2026, 4:00 PM ET)

Updated Oct 16, 2026, 4:00 PM ET

What changed since yesterday

ACIU dips 2.4% to $2.39, a 1-month low. Closed at $2.39, -2.45% vs the prior close of $2.45. Day range $2.38–$2.47, opened at $2.45.

Last close$2.39-2.45%

Day range2.38–2.47

Open2.45

Volume126.85K

52-week range2.10–4.00

Avg volume (20d)217.91K

ACIU daily analysis — what happened

A plain-English, data-only note written after every US trading day. Newest first; older days stay archived below.

Oct 16, 2026 — ACIU dips 2.4% to $2.39, a 1-month low

Closed at $2.39, -2.45% vs the prior close of $2.45. Day range $2.38–$2.47, opened at $2.45.
Volume was 126.85K shares, 0.6x its 50-day average of 208.11K.
Price is -9.5% vs its 50-day average ($2.64) and -14.1% vs its 200-day average ($2.78).
52-week range $2.10–$4.00; today's close sits at 15% of that range, 40.2% below the 52-week high.

Oct 15, 2026 — ACIU rises 2.1% to $2.45

Closed at $2.45, +2.08% vs the prior close of $2.40. Day range $2.38–$2.46, opened at $2.43.
Volume was 86.90K shares, 0.4x its 50-day average of 209.27K — lighter than usual.
Price is -7.2% vs its 50-day average ($2.64) and -12.0% vs its 200-day average ($2.79).
52-week range $2.10–$4.00; today's close sits at 19% of that range, 38.7% below the 52-week high.

Oct 14, 2026 — ACIU ends flat (+0.0%) to $2.40, 5 down days in a row

Closed at $2.40, +0.00% vs the prior close of $2.40. Day range $2.35–$2.41, opened at $2.37.
Volume was 209.70K shares, 1.0x its 50-day average of 207.20K.
Price is -8.9% vs its 50-day average ($2.64) and -14.0% vs its 200-day average ($2.79).
52-week range $2.10–$4.00; today's close sits at 16% of that range, 40.0% below the 52-week high.
That makes 5 straight losses.

Oct 13, 2026 — ACIU dips 2.0% to $2.40, a 1-month low, 4 down days in a row

Closed at $2.40, -2.04% vs the prior close of $2.45. Day range $2.39–$2.44, opened at $2.43.
Volume was 194.90K shares, 0.9x its 50-day average of 205.66K.
Price is -8.8% vs its 50-day average ($2.63) and -14.1% vs its 200-day average ($2.79).
52-week range $2.10–$4.00; today's close sits at 16% of that range, 40.0% below the 52-week high.
That makes 4 straight losses.

Oct 12, 2026 — ACIU dips 2.0% to $2.45, a 1-month low, 3 down days in a row

Closed at $2.45, -2.00% vs the prior close of $2.50. Day range $2.42–$2.50, opened at $2.50.
Volume was 148.50K shares, 0.7x its 50-day average of 207.27K.
Price is -6.8% vs its 50-day average ($2.63) and -12.4% vs its 200-day average ($2.80).
52-week range $2.10–$4.00; today's close sits at 19% of that range, 38.7% below the 52-week high.
That makes 3 straight losses.

Oct 9, 2026 — ACIU dips 2.0% to $2.50, a 1-month low

Closed at $2.50, -1.96% vs the prior close of $2.55. Day range $2.47–$2.59, opened at $2.55.
Volume was 271.30K shares, 1.3x its 50-day average of 206.76K.
Price is -4.7% vs its 50-day average ($2.62) and -10.7% vs its 200-day average ($2.80).
52-week range $2.10–$4.00; today's close sits at 21% of that range, 37.5% below the 52-week high.

Oct 8, 2026 — ACIU dips 0.8% to $2.55

Closed at $2.55, -0.78% vs the prior close of $2.57. Day range $2.50–$2.61, opened at $2.57.
Volume was 231.90K shares, 1.1x its 50-day average of 203.35K.
Price is -2.7% vs its 50-day average ($2.62) and -9.0% vs its 200-day average ($2.80).
52-week range $2.10–$4.00; today's close sits at 24% of that range, 36.3% below the 52-week high.

Oct 7, 2026 — ACIU rises 2.0% to $2.57

Closed at $2.57, +1.98% vs the prior close of $2.52. Day range $2.50–$2.59, opened at $2.52.
Volume was 125.10K shares, 0.6x its 50-day average of 202.93K.
Price is -1.8% vs its 50-day average ($2.62) and -8.4% vs its 200-day average ($2.81).
52-week range $2.10–$4.00; today's close sits at 25% of that range, 35.8% below the 52-week high.

Oct 6, 2026 — ACIU slides 7.0% to $2.52, 3 down days in a row

Closed at $2.52, -7.01% vs the prior close of $2.71. Day range $2.51–$2.72, opened at $2.72.
Volume was 277.80K shares, 1.4x its 50-day average of 199.99K.
Price is -3.5% vs its 50-day average ($2.61) and -10.2% vs its 200-day average ($2.81).
52-week range $2.10–$4.00; today's close sits at 22% of that range, 37.0% below the 52-week high.
That makes 3 straight losses.

Oct 5, 2026 — ACIU dips 0.6% to $2.71

Closed at $2.71, -0.55% vs the prior close of $2.72. Day range $2.65–$2.74, opened at $2.68.
Volume was 221.40K shares, 1.1x its 50-day average of 203.25K.
Price is +4.0% vs its 50-day average ($2.61) and -3.5% vs its 200-day average ($2.81).
52-week range $2.10–$4.00; today's close sits at 32% of that range, 32.2% below the 52-week high.

Oct 2, 2026 — ACIU slides 3.0% to $2.72

Closed at $2.72, -3.02% vs the prior close of $2.81. Day range $2.69–$2.88, opened at $2.84.
Volume was 320.20K shares, 1.6x its 50-day average of 198.43K.
Price is +4.9% vs its 50-day average ($2.60) and -3.1% vs its 200-day average ($2.81).
52-week range $2.10–$4.00; today's close sits at 33% of that range, 31.9% below the 52-week high.
SEC filings that day: 6-K.

Every SEC filing by or about ACIU in the last 120 days, explained in plain English. Updated daily, with a same-day refresh for new filings.

Oct 9, 2026 · Form 3/A — 3/A filing

3/A filing

Oct 9, 2026 · Form 3 — New insider holdings

Initial insider ownership statement (Form 3) — a new director, officer or 10% owner disclosed their holdings

Oct 2, 2026 · Form 6-K — Report from a foreign company (6-K)